Week Five of the Iran War: A Maritime Intelligence Breakdown

At a Glance

• Transit through the Strait of Hormuz increased during the week, but only under Iran’s permission-based system rather than open commercial navigation.
• A second, Oman-linked transit corridor emerged alongside the IRGC-controlled route, with vessels moving along the southern coastline under early-stage diplomatic coordination.
• Bandar Abbas revealed a structured AIS-dark logistics model, balancing outbound energy exports, prioritizing food imports, and continuing China-linked trade.
• Iranian crude and refined product exports remained active, supported by dark loading activity at Kharg Island, Bandar Abbas, and sanctioned tanker movements.
• Iranian cargo on water rose from roughly 174.2 million barrels to approximately 184 million barrels within the week’s reporting.
• Russian exports remained active, but Ust-Luga’s disruption deepened, with only one shipment recorded in seven days after repeated UAV attacks.
• Russian flows continued adapting through sanctioned and dark fleet routes, including resumed crude deliveries to Cuba and legal ambiguity around other shipments.
• Jet fuel supply tightened sharply following refinery strikes, with tanker availability dropping significantly and exposing aviation markets to supply risk.
• Gulf security risk escalated beyond chokepoints, with consecutive attacks on laden tankers near Dubai and off Ras Laffan.
• Port disruption remained elevated across Gulf and external hubs, reinforcing continued rerouting pressure and scheduling instability.
• The maritime system is still functioning, but through controlled access, dark operations, infrastructure disruption, and growing exposure across multiple critical nodes.

The Fifth Week of the Iran War at Sea

Five weeks into the conflict, the maritime system is no longer defined by simple restriction. It is being managed.

Transit through the Strait of Hormuz increased over the course of the week, with movement continuing under a permission-based model that now includes both the IRGC-controlled northern corridor and an emerging southern route along the Omani coastline.

At the same time, new visibility into Bandar Abbas showed how that system works in practice. Energy exports continued, food imports were prioritized, and China-linked container trade remained active. Much of it moved under AIS-dark conditions tightly linked to controlled access through Hormuz.

Beyond the Strait, the operating environment became more exposed. Iranian exports remained active, Russian exports continued under sharper infrastructure strain, and Yanbu’s role as a bypass route continued to grow. At the same time, jet fuel supply tightened following refinery disruption, and the threat profile expanded from transit corridors to anchored and staging vessels inside Gulf waters.

What emerged this week was a maritime system still moving, but through a narrower, more controlled, and more vulnerable operating model.

Hormuz Throughput Rises Under Control

The clearest shift this week was the increase in confirmed crossings through the Strait of Hormuz.

On March 29, only two AIS-transmitting vessels exited the Gulf and one entered. By March 30, confirmed crossings rose to six. By March 31, they reached 11. On April 1, transits climbed again to 16, marking a third consecutive daily increase.

This is not a return to open transit.

Throughout the week, the dominant model remained the same. Vessels primarily moved through the Iranian-controlled corridor north of Larak Island, hugging Iranian territorial waters rather than using the standard commercial lanes. SAR imagery repeatedly showed vessels staged north of Larak, likely awaiting or preparing for controlled transit. 

At the same time, a second transit corridor emerged along the southern side of the Strait, with vessels moving along the Omani coastline. Between April 2 and April 5, multiple vessels transited this route, beginning with three Omani-operated vessels — two VLCCs and one LNG carrier — marking the first confirmed use of the southern pathway and the first LNG transit since the war began.

Subsequent movements included additional eastbound crossings and a coordinated cluster of transits on April 4, indicating structured scheduling rather than isolated passage. Iran and Oman have also initiated discussions to formalize navigation rules, suggesting that this southern route is being integrated into a broader, permission-based transit framework rather than operating independently.

A significant share of transits through Hormuz involved sanctioned vessels, falsely flagged tankers, or operators tied directly or indirectly to Iranian trade. 

Outbound movements were concentrated in cargoes that benefited Iran directly or operationally. Bulk carriers carrying agricultural commodities, containerized goods, and dry bulk dominated the exits. Inbound movements were led by sanctioned, Iran-linked tankers and other cargoes aligned with the controlled system.

This confirms that throughput is rising, but access remains filtered. Hormuz is operating as a permission-based corridor that benefits approved cargoes, aligned operators, and sanctioned networks already adapted to reduced-visibility movement.

Bandar Abbas Reveals the Controlled System

This week’s most important operational signal came from Bandar Abbas.

Activity at Shahid Rajaei port provided a direct view into how Iran’s maritime system is functioning under wartime conditions. A total of 24 AIS-dark vessels were identified across the oil, bulk, and container terminals, all assessed to be operating under Iran-controlled access through Hormuz.

The oil terminal showed two tankers loading dirty petroleum products for export, with a total volume assessed at roughly 700 thousand barrels. The bulk terminal showed eight vessels discharging an estimated 375,000 to 500,000 tonnes of grain, corn, and agricultural inputs. The container terminal showed 14 vessels with an estimated 55,000 to 90,000 TEU in motion.

This indicates that Iran is keeping outbound petroleum flows active, prioritizing inbound food supply, and preserving China-linked trade through a structured logistics model. In this model, smaller feeder vessels appear to discharge Chinese-manufactured goods, machinery, and chemicals inbound, then load Iranian petrochemicals, minerals, and dried goods outbound.

Bandar Abbas is now functioning as one of the core nodes of Iran’s wartime maritime model. Access is managed, visibility is suppressed, and trade continues.

Iranian Exports Continue Under Dark and Controlled Conditions

Iranian exports remained active throughout the week across both crude and refined product segments.

On March 30, floating storage was estimated at approximately 174.2 million barrels, including 158.6 million barrels of crude, 13.9 million barrels of clean petroleum products, and 7.3 million barrels of dirty petroleum products. By March 31, cargo on water rose to approximately 184 million barrels, including 163 million barrels of crude and condensates, 13.22 million barrels of clean petroleum products, and 7 million barrels of dirty petroleum products.

Kharg Island remained an active loading node.

EO imagery from March 29 showed five tankers loading at Kharg, including three VLCCs, one Suezmax, and one Aframax, with an estimated total loading volume of approximately 7.7 million barrels. 

The following day’s reporting showed that three crude tankers had departed on March 29 carrying a combined estimated 4.7 million barrels. All three operated without AIS transmission during both loading and departure. One was flagged to Nicaragua, and two were Iranian-flagged. All had documented histories linking dark Gulf operations with dark activity in the Malaysia region, and all were sanctioned.

Additional imagery from April 2 identified six non-AIS transmitting tankers loading simultaneously at Kharg Island, supported by auxiliary servicing vessels. Multi-source analysis confirmed the identities and behavioral patterns of several of these vessels, including sanctioned tankers with extensive histories of AIS manipulation, identity changes, and ship-to-ship operations linked to Iranian export networks.

Refined product exports also continued. A 120-meter OFAC-sanctioned product tanker sailing under a fraudulent Aruba flag reported loading 53.1 thousand barrels of fuel oil at Bandar Abbas on March 28 and then proceeded toward Fujairah. Satellite imagery supported the reported loading activity.

The week also produced a politically significant shift in destination flows. A sanctioned Aframax, PING SHUN (IMO 9231901), flying the false flag of Eswatini and carrying roughly 600,000 barrels of Iranian crude, was reported en route from Kharg Island to Vadinar, India, potentially marking the first Iranian oil delivery to India since May 2019. The voyage was linked to U.S. General License U, issued on March 20, though the vessel-specific sanctions and operator designations create clear legal complexity around the transaction.

Taken together, Iran’s exports are continuing through a mix of dark operations, controlled transit, sanctioned vessels, and offshore logistics networks. The system is constrained, but it remains active.

Russian Exports Continue Under Increasing Infrastructure Pressure

Russian oil flows remained substantial during the week, but the pressure on export infrastructure became more acute.

Russian oil on water was estimated at approximately 237.75 million barrels, including 115.9 million barrels of crude and condensate, 51.37 million barrels of clean petroleum products, and 28.07 million barrels of dirty petroleum products. Top destinations remained India, China, Turkey, and Singapore.

These flows are now occurring alongside sharper infrastructure vulnerability.

Ust-Luga sustained five UAV attacks in seven days. Those repeated attacks raised concerns about the continuity of Russian export flows from the Baltic. By March 31, only one export event had been recorded in seven days, totaling approximately 730 thousand barrels. March 2026 was described as the lowest export month from Ust-Luga in at least 12 months.

Russian flows are still adapting. A documented crude shipment to the Philippines involved a Sierra Leone-flagged crude tanker that loaded 758.4 thousand barrels of ESPO blend crude at Port Kozmino on March 14 and discharged at Petron Bataan Refinery in the Philippines on March 25. This appears to be the first Russian crude shipment to the Philippines since the start of the Ukraine war.

In addition, this shipment seems to fall outside the stated U.S. OFAC General License 134 waiver window, suggesting an increasingly improvised export environment. 

Another shipment marked the first documented Russian crude delivery to Cuba since late December 2025, carried by a Russian-flagged tanker with a history of identity manipulation, flag hopping, and obfuscation, even though it maintained continuous AIS during the voyage.

The vessel departed Primorsk on March 8 and arrived in Matanzas, Cuba, on April 1, 2026. The cargo totaled approximately 749.5 thousand barrels of Urals crude.

The broader ownership picture also shifted. Analysis of tankers calling at Russia from March 1 to 25 showed that 67% of crude was shipped on tankers sanctioned by the U.S., EU, or UK. Other or unsanctioned dark fleet tankers accounted for 21%, while Greece-owned ships accounted for 12%, one of the lowest levels on record in the reporting provided.

Russian exports have not stopped, but they are operating through a system under more strain, with greater infrastructure exposure, tighter enforcement complexity, and deeper reliance on sanctioned or opaque shipping structures.

Export Flows Concentrate Across Fewer Routes

As Hormuz remained constrained, alternative routes became more important.

Yanbu remained central to that shift. Early in the week, it was described as operating as the primary Gulf bypass, with roughly 7 million barrels per day moving through the Saudi route at full East-West pipeline capacity. 

Saudi crude exports from Yanbu reached 3.3 million barrels per day in March, the highest monthly pace in records going back to 2017, and far above February’s 800,000 barrels per day.

At the same time, Iraqi exports are under pressure. Shipments via Ceyhan averaged 135,000 barrels per day in March, down from 236,000 barrels per day in the prior month. Meanwhile, total Iraqi exports plunged by 3 million barrels per day in March to 645,000 barrels per day.

This week, a significant concern emerged. Hormuz, Ust-Luga, and Yanbu were all under direct or escalating pressure. If all three were disrupted simultaneously, combined export losses could reach approximately 27.15 million barrels per day. The broader implications included severe freight inflation, a rapid jump in Brent prices, tighter stress across aviation and manufacturing, and a lower threshold for direct military intervention to reopen major corridors.

Even without that scenario, the system is already operating with reduced flexibility as alternative corridors absorb more volume.

Jet Fuel Supply Tightens Under Sustained Disruption

Jet fuel remains one of the most exposed segments in the current operating environment.

The March 19 strikes on Kuwait’s Mina Al-Ahmadi and Mina Abdulla refineries continue to affect roughly 10% of global seaborne jet fuel exports. At the same time, the number of LR1 and LR2 tankers carrying jet fuel dropped from 78 on March 20 to 22 by March 28, while global demand remains approximately 7.9 million barrels per day.

This is translating into a supply constraint rather than a pricing effect. Jet fuel cannot be stored long-term without degradation, which limits the system’s ability to absorb disruption through inventory.

Europe remains particularly exposed, with France, the UK, the Netherlands, and Belgium among the largest importers of Kuwaiti jet fuel.

As a result, disruption is moving beyond pricing pressure and into availability risk, with potential implications for aviation operations if supply continuity is not restored.

Maritime Security Incidents 

On March 31, a drone strike targeted a laden VLCC approximately 31 nautical miles northwest of Dubai. The vessel was carrying roughly 2 million barrels of crude. The fire onboard was later contained without casualties or reported pollution.

On April 1, a second serious incident followed. The Panama-flagged tanker AQUA 1 (IMO 9573660), on charter to Qatar Energy, was struck by two Iranian cruise missiles around 17 nautical miles north of Ras Laffan, Qatar. One missile caused a fire that was later extinguished. Another remained unexploded in the engine room. All 21 crew members were evacuated safely, and no environmental damage was reported.

According to the UKMTO, this was the 24th maritime incident logged since February 28 across the Middle East Gulf, Strait of Hormuz, and Gulf of Oman, including 16 confirmed attacks and eight suspicious events.

On April 4, the Liberian-flagged container vessel MSC ISHYKA was struck by an IRGC drone while at berth in Khalifa Bin Salman Port, Bahrain, with fire reported onboard. The vessel had entered port the previous day and was reportedly targeted based on ownership claims.

These incidents show that exposure now extends to berthed vessels and port infrastructure, not only transiting or anchored ships.

Port Friction Remains Elevated

Port activity this week reflected continued operational strain rather than recovery.

Inside the Gulf, disruption indicators remained elevated at Jebel Ali, Port Khalid, Shuwaikh, and Khalifa Bin Salman. These included transshipment rollovers, delay cases, and port-of-destination changes, often far above seven-day averages.

Outside the Gulf, Karachi, Khor Fakkan, and Salalah also showed ongoing friction. Karachi recorded both rollovers and destination changes above recent averages. Khor Fakkan saw a sharp jump in destination changes. Salalah’s delay and rollover counts remained significant even where they were below recent seven-day averages, indicating that external hubs continue to absorb rerouting pressure.

These patterns point to a wider operating environment in which routing decisions remain fluid, schedules are unstable, and secondary hubs are carrying more of the system’s adjustment burden. Even where ports remain active, the network around them is becoming less predictable.

Outlook

Week five marked a clear shift from constrained closure to managed throughput.

The emergence of a second, Oman-linked transit corridor suggests that access is no longer confined to a single route, but is instead evolving into a multi-lane system managed through a combination of control, coordination, and bilateral negotiation.

At the same time, Bandar Abbas showed that Iran has built a functioning maritime model under conflict conditions. Energy exports continue, food imports are prioritized, and China-linked trade remains active. Much of it operates under dark or partial-visibility conditions.

Iranian exports remain resilient, and Russian exports remain active, but Ust-Luga’s disruption now appears material rather than temporary. Alternative routes such as Yanbu are carrying more of the system’s weight, which makes them more strategically important and more exposed. Jet fuel markets are already showing the effects of this disruption, with tightening supply translating into availability risk rather than price pressure alone.

The week also expanded the threat picture. Consecutive tanker attacks near Dubai and Ras Laffan showed that maritime risk is spreading beyond chokepoints and into the wider Gulf operating environment.

The system is still moving. But it is moving through a narrower set of routes, darker logistics patterns, and more exposed infrastructure.