IMO Chief Tells Shipping to Avoid Hormuz After Fresh Vessel Attacks
The maritime agency's warning adds institutional weight to a shipping crisis that has kept Gulf crude flows far below pre-war levels even during the ceasefire period.
The International Maritime Organization's secretary-general advised ships to avoid the Strait of Hormuz on Wednesday (2026-07-08) following a fresh wave of vessel attacks, marking a formal escalation by a global shipping authority in a crisis that has disrupted energy flows since the US-Iranian conflict began. ICE Brent crude front-month was trading at $75.90 on Thursday (2026-07-09), down 0.5% on the day, reflecting markets still pricing some prospect of resolution even as the latest escalation threatens to reverse what little traffic had returned.8
The IMO warning formalises what shipping data had already shown. Commercial traffic through Hormuz slowed to near standstill on Monday (2026-05-18) after tensions escalated sharply, with vessel tracking data showing just one ship exiting the Gulf while two entered over a 24-hour period, according to The Vibes. The episode preceded a partial recovery, but the fundamental instability in the strait never cleared.6
Even during brief periods when tankers began moving, tracking compliance was poor. Three crude oil supertankers carrying a combined 6 million barrels of Gulf crude exited the strait with their tracking systems switched off, according to shipping data from Kpler and LSEG released on Monday (2026-05-18). Disabling AIS transponders is a standard response to attacks on identifiable vessels, but it reduces the market's ability to assess actual flow volumes.4
A clearer picture emerged later in May, when three supertankers were confirmed crossing Hormuz on Wednesday (2026-05-20) carrying oil for Asian markets after waiting in the Gulf for more than two months. Among them was the South Korean-flagged VLCC Universal Winner, carrying 2 million barrels of Kuwaiti crude loaded on March 4, and a Chinese-flagged VLCC, the Yuan Gui Yang, loaded with 2 million barrels of Iraqi Basrah crude on February 27, the day before the US-Israeli war with Iran started.3
Saudi Aramco gave the starkest commercial read on the disruption. Aramco's chief executive said the company expected to supply about 70% of its usual crude output while Hormuz remained contested, and warned of "catastrophic consequences" if the blockade persisted. ICE Brent crude front-month fell roughly 14% on Tuesday (2026-05-19) to around $85 per barrel as initial ceasefire news prompted selling, illustrating how quickly markets move on diplomatic signals rather than physical data.2
Analysts at Montel described energy markets as "fragile" even when the ceasefire was holding, noting on Wednesday (2026-05-20) that reports of vessel seizures by Iran's military underlined the gap between a diplomatic pause and physical security for shipping. The Economist's reporting on the clearing operation noted that Houthi forces had vowed to resume attacks in solidarity with Iran, and that traffic had not returned to pre-crisis levels even after US Navy operations in the strait.1,7
Current prices sit materially below those May levels. ICE Brent crude front-month at $75.90 on Thursday (2026-07-09) suggests markets had priced in a more lasting resolution than the June memorandum of understanding delivered. The JKM Asian LNG benchmark was at $16.57 per MMBtu on Thursday (2026-07-09), with Qatari cargo flows directly exposed given Qatar's position as a major LNG exporter through the strait. ICE Endex TTF front-month held at €50.02 on Thursday (2026-07-09), with European gas markets facing potential supply disruption if Qatari cargo diversions extend into the coming weeks.8
The IMO advisory does not carry operational force — ships are not legally prohibited from transiting — but it shapes decisions by insurance underwriters, charterers and flag state authorities. War-risk premiums on vessels transiting Hormuz had spiked sharply after the conflict began and have remained elevated throughout. Higher insurance costs feed directly into the delivered economics of crude and LNG cargoes for European buyers.5,4
The hundreds of ships and thousands of mariners stranded in the Gulf by the conflict were waiting for conditions to stabilise long before the June ceasefire, according to the Economist, which described the strait as "the sole waterway" for Gulf energy exports. Iran's retention of effective harrassment capability — fast-attack boats, coastal missiles and drone strikes — against commercial traffic means the physical risk has not receded in step with diplomatic announcements.5
Whether Iran's return to targeting commercial shipping prompts a reassessment of negotiating positions or a further tightening of the chokepoint shapes the ICE Brent crude front-month trajectory and European LNG import costs for the weeks ahead.8,1