US Sanctions on Singapore-Linked Entities: Iranian Oil Trade Case Study

by | Dec 5, 2025 | Uncategorized | 0 comments

Executive Summary

In November 2025, the United States imposed sanctions on multiple Singapore-linked entities as part of a broader crackdown on Iranian oil trade networks. This case study examines the implications for Singapore’s maritime sector, analyzes the geopolitical context, and proposes strategic solutions for businesses and policymakers.

Case Study: Strasse Link and the Shadow Fleet Network

Background

The sanctions targeting Strasse Link Pte. Ltd. and its directors exemplify how Singapore’s position as a global maritime hub has made it vulnerable to entanglement in sanctioned trade networks. The company provided pilotage services to Iranian-backed tankers carrying crude oil through the Straits of Malacca on 13 occasions between January and August 2025.

Modus Operandi

The sanctioned entities employed sophisticated techniques to circumvent existing sanctions:

Ship-to-Ship (STS) Transfers: Vessels discharged Iranian crude oil through ship transfers just outside Singapore’s port limits, exploiting international waters to avoid direct port oversight.

Shadow Fleet Operations: Companies like Anbo Shipping operated as part of Iran’s “shadow fleet,” using deceptive shipping practices including flag-hopping, falsified documentation, and transponder manipulation to obscure cargo origins.

Corporate Layering: Complex ownership structures involving Singapore-registered companies with overseas operations (like Hengyang Petrochemical Logistics) created opacity that complicated enforcement efforts.

Volume and Scale: The Strasse Link case alone allegedly facilitated over 20 million barrels of Iranian crude oil transfer, demonstrating the significant scale of these operations.

Key Players Sanctioned

Singapore-Based Operations:

  • Maritime service providers (Strasse Link, Anbo Shipping)
  • Shipping companies and their vessels (Anglo Premier Shipping/APS 9, Logos Marine/Pioneer 92)
  • Petrochemical trading firms (Haresh Petrochem Singapore)

Individual Directors: Both Singaporean citizens and permanent residents have been sanctioned, including company directors and senior managers who knowingly facilitated transactions.

International Network: The sanctions reveal connections between Singapore entities and broader networks spanning China, India, and Panama-flagged vessels.

Financial Impact

According to US government estimates, these networks generated hundreds of millions of dollars for the Iranian regime. Individual companies like the India-based parent of Haresh Petrochem imported approximately $10 million in Iranian petrochemical products between January 2024 and February 2025.

Geopolitical Context and Outlook

Trump Administration’s “Maximum Pressure” Campaign

The sanctions represent a significant escalation in US enforcement under President Trump’s second term. Following a national security memorandum signed in February 2025, the administration has directed Treasury to aggressively target sanction violators through economic pressure.

This marks a departure from potential sanction relief that had been discussed during nuclear negotiations and signals a return to the pre-2021 enforcement posture.

Outlook for 2026 and Beyond

Increased Enforcement Intensity: The November 2025 designations, which included some of the largest buyers of Iranian petrochemicals by volume, suggest the US is targeting higher-value nodes in the supply chain. Expect continued pressure on:

  • Major petrochemical buyers and traders
  • Maritime service providers in key chokepoints
  • Financial institutions facilitating payments
  • Insurance and re-insurance providers

Regional Implications: Singapore’s strategic location at the Straits of Malacca makes it a critical transit point for Iranian oil destined for Asian markets, particularly China. As the US tightens enforcement, pressure on Singapore’s regulatory framework will intensify.

Secondary Sanctions Risk: Companies and individuals conducting business with sanctioned entities face exposure to secondary sanctions, potentially cutting them off from the US financial system. This creates cascading compliance risks throughout supply chains.

Technology and Detection: Advances in satellite monitoring, AIS tracking, and financial surveillance mean that previously covert operations are increasingly detectable. The US government’s ability to identify 13 specific pilotage incidents in an eight-month period demonstrates enhanced monitoring capabilities.

China-US Tensions: Many Iranian oil shipments ultimately reach Chinese buyers. The sanctions on Singapore entities occur within broader US-China strategic competition, potentially complicating Singapore’s position as it maintains relationships with both powers.

Impact on Singapore

Immediate Impacts

Reputational Risk: Singapore’s brand as a transparent, well-regulated maritime and financial hub faces potential damage from repeated sanctions designations. International businesses may question the adequacy of Singapore’s compliance frameworks.

Business Disruption: At least 10 Singapore-linked entities now face asset freezes and transaction prohibitions in the US. This affects:

  • Company operations and cash flow
  • Employment for local staff
  • Business relationships with global counterparties
  • Access to US dollar clearing systems

Individual Consequences: Singaporean citizens and permanent residents on the sanctions list face severe personal restrictions, including:

  • Asset freezes on US-based holdings
  • Travel restrictions and visa complications
  • Career limitations in international business
  • Potential criminal liability if sanctions violations continue

Industry Spillover: Maritime service providers, shipping agents, and commodity traders not directly sanctioned may face increased scrutiny, higher compliance costs, and reluctant counterparties conducting enhanced due diligence.

Strategic and Long-Term Impacts

Regulatory Pressure: Singapore may face diplomatic pressure from the United States to strengthen enforcement of international sanctions. This could require:

  • Enhanced monitoring of ship-to-ship transfers in Singapore waters
  • Stricter licensing requirements for maritime services
  • Mandatory reporting obligations for suspicious transactions
  • Greater information sharing with US authorities

Sovereignty Considerations: Increased US extraterritorial enforcement raises questions about regulatory sovereignty. Singapore must balance international compliance expectations with its independent foreign policy, including maintaining relationships with Iran and China.

Economic Competitiveness: Stricter compliance requirements may increase costs for legitimate businesses operating in Singapore’s maritime sector. Competing ports with less stringent oversight could gain market share if compliance burdens become excessive.

Regional Hub Status: Singapore’s position as Asia’s premier maritime hub depends on reliability, transparency, and rule of law. Repeated sanctions incidents could erode confidence, though Singapore’s overall governance standards remain strong.

Bilateral Relations: The sanctions may strain US-Singapore relations if not managed carefully. Singapore will need to demonstrate good faith efforts to address US concerns while preserving its multi-aligned foreign policy approach.

Sectoral Vulnerabilities

Maritime Services: Singapore’s extensive ship chandling, pilotage, bunkering, and port services sectors are particularly exposed to sanctions risk given the volume of Iranian vessels transiting regional waters.

Petrochemical Trading: Singapore hosts numerous commodity trading firms dealing in petroleum products. The opacity of petrochemical supply chains creates compliance challenges.

Financial Services: Banks and financial institutions in Singapore must enhance sanctions screening to avoid facilitating prohibited transactions or processing funds for designated entities.

Solutions and Recommendations

For Singapore Government

Regulatory Framework Enhancement

Strengthen maritime oversight by implementing mandatory pre-arrival notification systems for all vessels entering Singapore waters, with enhanced scrutiny for high-risk flags and operators. Develop specialized capabilities within the Maritime and Port Authority to monitor ship-to-ship transfers in Singapore’s approaches using satellite technology, AIS data analytics, and aerial surveillance. This should include real-time tracking of vessels with suspicious transponder patterns or those operating in known Iranian oil routes.

Establish a dedicated inter-agency task force bringing together MPA, the Monetary Authority of Singapore, trade authorities, and intelligence services to coordinate sanctions enforcement. This body should maintain direct communication channels with US Treasury’s Office of Foreign Assets Control and other international partners to receive real-time intelligence on emerging threats.

Introduce legislative amendments to strengthen penalties for sanctions violations, ensuring that fines and criminal consequences create genuine deterrence. Current penalties may be insufficient given the hundreds of millions of dollars flowing through these networks. Consider implementing corporate liability provisions that hold companies accountable for inadequate compliance systems.

International Cooperation

Develop a bilateral framework with the United States for enhanced information sharing on sanctions enforcement. This could include secondment programs where Singapore officials work with OFAC to better understand US sanctions methodology and priorities. Regular joint working groups should review emerging sanctions risks and coordinate enforcement actions.

Strengthen regional cooperation through ASEAN mechanisms to establish consistent approaches to sanctions compliance across Southeast Asian ports. The Straits of Malacca transit traffic affects Malaysia and Indonesia as well, requiring coordinated regional responses. A unified approach would prevent sanctions evasion through jurisdiction shopping.

Engage proactively with Chinese authorities, acknowledging that much Iranian oil ultimately reaches Chinese buyers. Singapore should position itself as a responsible intermediary that can facilitate legitimate trade while preventing sanctions evasion, rather than being caught between competing US and Chinese interests.

Industry Engagement

Launch a comprehensive guidance program for maritime service providers, shipping companies, and trading firms on sanctions compliance best practices. This should include sector-specific red flags, case studies of violations, and practical due diligence procedures. The government should fund training programs and potentially subsidize compliance technology for small and medium enterprises.

Establish a confidential reporting mechanism where companies can seek guidance on potentially suspicious transactions without fear of immediate enforcement action. This safe harbor approach encourages voluntary disclosure and helps businesses navigate complex compliance scenarios.

Create an industry certification program recognizing companies with robust sanctions compliance frameworks. Certified firms could receive preferential treatment in government contracts and international recognition, creating competitive advantages for compliance investment.

For Singapore-Based Maritime Companies

Enhanced Due Diligence Protocols

Implement comprehensive vessel screening before accepting any service engagement. This must go beyond basic sanctions list checking to include:

  • Historical AIS tracking analysis to identify vessels with suspicious movement patterns
  • Ownership verification through multiple registries and beneficial ownership databases
  • Cross-referencing vessel names against known shadow fleet identifiers
  • Verification of cargo declarations against typical vessel routes and capacity
  • Assessment of flag state reputation and compliance standards

Develop relationship mapping capabilities to understand the full corporate structure of clients. Many sanctioned entities operate through complex webs of holding companies, subsidiaries, and affiliated entities. Companies should invest in corporate intelligence tools and subscriptions to specialized databases tracking sanctions risks.

Conduct regular audits of existing client relationships, recognizing that sanctions lists are dynamic and previously compliant clients may become sanctioned. Implement automated alerts for any changes to sanctions designations affecting current business relationships.

Operational Best Practices

Establish strict policies prohibiting services to vessels that refuse to provide transparent information about ownership, cargo, and ultimate destinations. Train frontline staff to recognize common red flags including:

  • Requests for unusual payment arrangements (especially cash or cryptocurrency)
  • Reluctance to provide standard documentation
  • Inconsistencies between stated and actual vessel operations
  • Pressure to expedite services without normal due diligence
  • Involvement of multiple intermediaries obscuring ultimate clients

Implement technology solutions for real-time monitoring of vessels under service. This includes satellite tracking, continuous AIS monitoring, and integration with global trade databases. Any deviations from stated routes or unexpected ship-to-ship transfers should trigger immediate review and potential service termination.

Maintain detailed records of all due diligence efforts, client communications, and decision-making processes. In the event of sanctions investigations, comprehensive documentation demonstrating good faith compliance efforts can be crucial for avoiding penalties or criminal liability.

Corporate Governance

Designate a senior executive with board-level responsibility for sanctions compliance. This person should have direct access to the CEO and authority to halt any transaction presenting unacceptable sanctions risk, regardless of revenue implications. Compliance cannot be relegated to junior staff without decision-making power.

Implement mandatory compliance training for all employees with at least annual refreshers. Training should be role-specific, with enhanced programs for sales, operations, and management personnel who directly engage with clients. Document all training completion and test comprehension.

Establish a compliance committee that reviews high-risk transactions before approval. This committee should include legal, operations, and business development perspectives to ensure balanced decision-making. Meeting minutes should document the rationale for accepting or rejecting questionable business.

Financial and Insurance Protection

Secure specialized sanctions liability insurance to protect against inadvertent violations. Standard marine insurance policies may not cover sanctions-related losses or legal defense costs. Work with insurance brokers familiar with sanctions risks to structure appropriate coverage.

Establish legal reserves to fund potential sanctions investigations or enforcement actions. Even companies that ultimately face no penalties may incur substantial legal and consulting costs during investigations. Adequate reserves prevent financial distress from compliance-related expenses.

Conduct regular external audits of sanctions compliance programs by qualified third-party firms. Independent validation of compliance systems provides both credibility with regulators and early identification of potential gaps before they lead to violations.

For Individual Shipping Professionals

Personal Due Diligence

Before accepting any position or directorship in maritime, petrochemical, or trading firms, conduct thorough research on the company’s business model and client base. Search for any past sanctions violations, regulatory actions, or adverse media coverage. Consider the following warning signs:

  • Significant business with high-risk jurisdictions (Iran, North Korea, Syria, Venezuela)
  • Rapid growth without transparent business development
  • Reluctance to discuss compliance procedures during interviews
  • Compensation structures heavily weighted toward bonuses tied to transaction volume
  • Limited or non-existent legal and compliance staff

Request detailed information about existing compliance programs before accepting positions. Reputable companies will have documented policies, regular training, and clear escalation procedures for compliance concerns. Absence of these systems indicates elevated personal risk.

Consult with legal counsel specializing in sanctions before accepting directorships or senior management roles in potentially exposed sectors. Legal advisors can review employment contracts to ensure appropriate indemnification provisions and help structure compensation to avoid perverse incentives around risky transactions.

Professional Conduct Standards

Refuse to participate in any transactions that lack transparent documentation or involve requests to circumvent normal procedures. Individuals sanctioned alongside Strasse Link face personal asset freezes, travel restrictions, and potential criminal liability. No employment opportunity justifies these personal consequences.

Maintain personal records of any compliance concerns raised internally and company responses. If management ignores warnings or pressures employees to proceed with questionable transactions, documentation of objections can be crucial for demonstrating lack of knowing participation if violations occur.

Join professional associations with established ethics standards and access to legal resources. Organizations like the Singapore Shipping Association can provide guidance on industry best practices and support for members facing compliance dilemmas.

Career Risk Management

Develop expertise in sanctions compliance as a professional competency. As enforcement intensifies, professionals who can demonstrate specialized knowledge in this area will have competitive advantages. Consider certifications from organizations like ACAMS (Association of Certified Anti-Money Laundering Specialists) with sanctions specializations.

Maintain diversified professional networks outside potentially exposed sectors. If sanctions violations force career changes, having established relationships in alternative industries facilitates transitions. Build transferable skills that have value beyond shipping and commodities trading.

Consider professional liability insurance if working in high-risk sectors. While such policies may not cover criminal sanctions violations, they can provide legal defense costs and protection against civil claims arising from employment activities.

For Trading and Petrochemical Companies

Supply Chain Transparency

Implement comprehensive cargo tracking from origin to final destination. This requires going beyond immediate suppliers to map entire supply chains, identifying:

  • Ultimate sources of petroleum and petrochemical products
  • All intermediaries and traders involved in transactions
  • Transportation routes and transshipment points
  • Storage and blending facilities that might obscure origins
  • Final buyers and end-use applications

Utilize blockchain or distributed ledger technologies to create immutable records of product provenance. Several maritime consortiums are developing blockchain solutions for trade documentation that could enhance transparency and reduce sanctions risks.

Require suppliers to provide certificates of origin with independent verification. Given sophisticated evasion techniques including document fraud and cargo blending, rely on multiple verification methods including chemical analysis, shipment tracking, and third-party inspections.

Financial Controls

Implement enhanced screening of all payments to identify indirect exposure to sanctioned parties. Many violations occur through seemingly legitimate intermediaries who obscure the ultimate beneficiaries of transactions. Screen not just direct counterparties but also:

  • Banks facilitating payments and their correspondent relationships
  • Insurance providers and reinsurers
  • Letters of credit issuers and confirming banks
  • Payment agents and escrow services

Avoid transactions involving complicated payment structures with multiple intermediaries, especially those routed through high-risk jurisdictions. Unusual payment arrangements are common red flags in sanctions evasion schemes.

Establish transaction size limits requiring enhanced approval for deals above certain thresholds. The $10 million in Iranian petrochemical imports by Haresh Petrochem’s parent company represented substantial exposure. Lower-value transactions may justify streamlined due diligence, but significant deals require comprehensive review.

Contractual Protections

Include robust sanctions compliance warranties in all contracts with suppliers and customers. These should require counterparties to represent that products do not originate from sanctioned sources and that parties are not subject to sanctions restrictions.

Implement material breach provisions allowing immediate contract termination if sanctions issues emerge. Include specific language preserving rights to terminate if counterparties are designated on sanctions lists or if products are found to have sanctioned origins.

Require indemnification for sanctions-related losses arising from counterparty misrepresentations. While indemnities from sanctioned entities may have limited practical value, they establish legal claims and demonstrate good faith compliance efforts.

Long-Term Strategic Solutions

Building a Sanctions-Resilient Maritime Ecosystem

Singapore has an opportunity to transform this challenge into a competitive advantage by establishing the world’s most robust sanctions compliance framework for maritime services. This would involve:

Regulatory Innovation: Develop a licensing system for maritime service providers with graduated tiers based on compliance sophistication. Basic license holders could serve low-risk vessels with standard due diligence, while premium license holders would undergo enhanced scrutiny but could serve higher-risk segments with appropriate controls. This creates market segmentation based on risk appetite while maintaining overall system integrity.

Technology Infrastructure: Invest in national maritime surveillance infrastructure integrating satellite imagery, AIS data, synthetic aperture radar, and artificial intelligence for pattern recognition. Singapore could develop proprietary algorithms detecting suspicious vessel behaviors and make this capability available to licensed service providers, creating an information advantage over competing ports.

Compliance as Competitive Advantage: Market Singapore as the premium jurisdiction for maritime services where robust compliance is the differentiator. Companies willing to pay marginal premiums for services in Singapore would gain assurance that their operations won’t expose them to sanctions risks. This positions Singapore at the high end of the market rather than competing on price with less-regulated ports.

Center of Excellence: Establish Singapore as the global center for maritime sanctions compliance expertise by:

  • Creating specialized academic programs at NUS and SMU focusing on trade sanctions and maritime law
  • Hosting annual international conferences bringing together regulators, industry, and legal experts
  • Developing certification programs recognized worldwide for maritime compliance professionals
  • Building consulting firms that export Singapore’s compliance expertise globally

Diplomatic and Strategic Positioning

Singapore must navigate complex geopolitical tensions while maintaining its role as a neutral, reliable maritime hub. This requires sophisticated diplomatic engagement:

Multi-Alignment Strategy: Singapore should continue its longstanding approach of maintaining productive relationships with all major powers. This means demonstrating good faith compliance with legitimate sanctions while resisting pressure to align completely with any single power’s foreign policy objectives. Singapore can comply with UN Security Council sanctions and respected international norms while maintaining nuanced positions on unilateral sanctions regimes.

Asian Financial Center Development: Diversify Singapore’s financial ecosystem to reduce dependence on US dollar clearing for regional trade. This doesn’t mean abandoning dollar-based finance, but rather developing parallel systems using other currencies (RMB, euro, yen) and potentially regional digital currencies for trade settlement. This provides alternatives if US sanctions overreach threatens legitimate business.

ASEAN Leadership: Position Singapore as the leading voice for practical, proportionate sanctions enforcement within ASEAN. Singapore’s credibility as a well-governed, transparent jurisdiction gives it standing to advocate for regional approaches that balance compliance obligations with economic realities and sovereignty considerations.

Humanitarian Safeguards: Advocate internationally for sanctions frameworks that minimize humanitarian impacts and preserve channels for legitimate trade. Singapore can draw on its reputation for principled governance to promote sanctions policies that achieve security objectives without excessive collateral damage to civilian populations or regional commerce.

Economic Diversification and Resilience

While maritime services will remain central to Singapore’s economy, reducing concentration in potentially vulnerable segments enhances overall resilience:

High-Value Maritime Services: Shift emphasis toward segments less exposed to sanctions risks, including:

  • Maritime technology and digitalization services
  • Ship design and engineering
  • Maritime legal and arbitration services
  • Marine insurance and risk management
  • Maritime education and training
  • Green shipping and sustainability consulting

These services generate high value with lower sanctions exposure than operational services like pilotage or bunkering for potentially risky vessels.

Clean Energy Transition: Accelerate Singapore’s positioning as a clean energy hub for hydrogen, ammonia, and renewable fuels. As global shipping decarbonizes, first-mover advantages in new energy infrastructure reduce dependence on fossil fuel trade vulnerable to geopolitical disruptions.

Digital Economy Expansion: Continue aggressive investment in Singapore’s digital economy, artificial intelligence, and technology sectors. Diversification beyond traditional maritime and financial services reduces systemic vulnerabilities while leveraging Singapore’s strengths in education, rule of law, and infrastructure.

Regional Integration: Deepen economic integration with ASEAN partners through trade agreements, infrastructure connectivity, and regional supply chains. Greater regional economic interdependence provides resilience against bilateral pressures while expanding Singapore’s effective economic footprint.

Legal and Regulatory Framework Modernization

Singapore should comprehensively update its legal framework to address evolving sanctions challenges:

Autonomous Sanctions Legislation: Consider developing Singapore’s own sanctions regime allowing implementation of international sanctions without requiring them to originate from the UN Security Council. This provides flexibility to align with international norms while maintaining decision-making sovereignty. Singapore could adopt sanctions in coordination with like-minded partners while retaining independence from any single power’s unilateral measures.

Extraterritorial Enforcement Limits: Establish clear boundaries on Singapore’s cooperation with foreign extraterritorial enforcement. While maintaining productive relationships with enforcement authorities worldwide, Singapore should resist enforcement approaches that inappropriately extend foreign jurisdiction over Singaporean persons and entities engaged in lawful conduct under Singapore law.

Corporate Liability Framework: Update corporate criminal liability provisions to ensure companies can be held accountable for sanctions violations while maintaining appropriate mens rea requirements. This should include:

  • Adequate procedures defense allowing companies to avoid liability by demonstrating robust compliance systems
  • Personal liability for directors who deliberately ignore sanctions risks
  • Deferred prosecution agreements enabling resolution of violations without destroying viable businesses
  • Clear guidance on voluntary disclosure benefits to encourage self-reporting

International Legal Cooperation: Negotiate mutual legal assistance treaties and information sharing agreements specifically addressing sanctions enforcement. Clear frameworks for cross-border cooperation reduce friction and arbitrary enforcement while protecting against inappropriate fishing expeditions.

Conclusion

The US sanctions on Singapore-linked entities represent both a challenge and an opportunity. In the short term, affected companies and individuals face significant disruptions, and Singapore’s reputation as a transparent, well-regulated hub faces scrutiny. The government must navigate complex geopolitical pressures while the private sector adapts to heightened compliance expectations.

However, Singapore’s longstanding commitment to rule of law, transparent governance, and international cooperation positions it well to address these challenges. By strengthening regulatory frameworks, enhancing industry compliance capabilities, and positioning itself as the premium jurisdiction for well-regulated maritime services, Singapore can emerge from this period with enhanced rather than diminished standing.

The key is recognizing that sanctions compliance is not merely a regulatory burden but a strategic imperative and potential competitive advantage. In an increasingly complex geopolitical environment, businesses and jurisdictions that can demonstrate robust, reliable compliance will command premiums while those with weak controls face marginalization.

For Singapore, the path forward requires balancing multiple imperatives: maintaining productive relationships with all major powers, upholding international norms and obligations, preserving sovereignty and independent decision-making, and ensuring continued prosperity for businesses and citizens. This is a familiar challenge for Singapore, which has successfully navigated great power competition throughout its history. The current sanctions issues, while serious, are manageable through the comprehensive, multi-layered approach outlined in this analysis.

Ultimately, Singapore’s response to these sanctions will define its role in an increasingly multipolar world. By combining robust compliance with diplomatic sophistication and economic innovation, Singapore can maintain its position as Asia’s premier international business hub while adapting to the realities of 21st century geopolitical competition.