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Iran Conflict 2026
25MAY

One ship through Hormuz in 24 hours

3 min read
13:55UTC

AIS vessel tracking data confirms what diplomatic language obscures: the Strait of Hormuz is effectively shut, with a single commercial transit recorded in a full day.

ConflictDeveloping
Key takeaway

Primary AIS data shows Hormuz is effectively closed; diplomatic framing overstates passage.

AIS (Automatic Identification System) monitoring data recorded one commercial cargo transit through the strait of Hormuz in the past 24 hours 1. The pre-war baseline was 30 to 50 daily transits carrying roughly 20 million barrels per day of crude and product exports. The diplomatic narrative of ships getting through collapses against this primary data.

Pakistan secured a second bilateral deal with Iran: 20 more vessels at two per day, bringing the total to approximately 40 Pakistani-flagged ships 2. Iran's state media framed it as a bilateral arrangement, not a concession on Hormuz sovereignty. Iran drew this distinction deliberately. Iran's five conditions for ending the war include permanent sovereignty over the strait; the Pakistan deal costs Tehran nothing on that legal question.

The IEA March report confirms nearly 20 million barrels per day of crude and product exports disrupted through Hormuz, substantially higher than the 8 mb/d production disruption commonly cited 3. Buried in the same report: demand growth revised down 210,000 barrels per day, an early recession signal. The Majlis toll bill is expected to be finalised this week. Passage would embed Hormuz control in Iranian domestic law, converting de facto IRGC control into a constitutional fact that no negotiator could concede.

Deep Analysis

In plain English

The Strait of Hormuz is a 33-kilometre-wide bottleneck in the Persian Gulf through which roughly 20% of the world's oil passes every day. In peacetime, 30 to 50 ships transit it daily. In the past 24 hours, one ship went through. Iran controls the strait because the narrow shipping channel runs through its territorial waters. It has been charging ships a toll of up to $2 million per vessel to pass. Most ships are not paying, and most are not transiting. The practical effect: oil, gas, and petrochemical supply chains are broken across Asia, Europe, and beyond. The IEA has released emergency reserves, but those cover about 20 days of the disruption at most.

Deep Analysis
Root Causes

Iran's control of Hormuz is not a wartime improvisation; it reflects decades of deliberate naval investment in asymmetric chokepoint denial capability. The IRGC Navy developed the toll system precisely because it understood Hormuz passage was its most durable strategic leverage.

The legal architecture underlying the closure combines de facto IRGC enforcement with Iran's domestic Majlis legislation and IMO notification. Each layer reinforces the others: IRGC control is enforceable, the Majlis bill makes it domestic law, and the IMO notification creates international legal precedent.

What could happen next?
  • Risk

    The IEA's 400 million barrel emergency reserve covers roughly 20 days of disruption; sustained closure beyond that point exhausts the buffer and triggers rationing.

    Short term · 0.75
  • Consequence

    Dow CEO's 250-275 day supply chain unwinding estimate means structural damage is locked in regardless of when the war ends.

    Medium term · 0.8
  • Risk

    Recession demand destruction already visible in IEA's -210,000 b/d revision may accelerate, masking the true supply shock until Hormuz reopens.

    Short term · 0.65
First Reported In

Update #51 · Iran hits aluminium plants; Hormuz emptying

International Maritime Organisation / UKMTO· 29 Mar 2026
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Different Perspectives
Lloyd's of London
Lloyd's of London
The Joint War Committee left Hormuz war-risk premiums at $10-14 million per voyage on 25 May, declining to move on Brent's 5% fall. The JWC's protocol requires a UN Security Council resolution or bilateral government certification letter before de-listing, and neither has arrived: a verbal understanding does not satisfy the formal condition the reinsurance market's treaty terms require.
Gulf Arab producers
Gulf Arab producers
Saudi Arabia and UAE depend on Hormuz for their own crude exports; Aramco CEO Nasser has warned no oil market recovery arrives until 2027 if the blockade continues past mid-June. Monday's $98.96 Brent settlement shortens nothing for Gulf producers without a signed instrument and a Pentagon mine-clearance timeline that runs up to six months post-ceasefire.
Qatar
Qatar
Qatar holds $12bn of frozen Iranian assets at the centre of the sequencing dispute but cannot release them without explicit US Treasury authorisation, given the original freeze was a US instrument. As the asset-holding state, Qatar's leverage is real but passive: it is the escrow holder, not the decision-maker, and any resolution requires US Treasury sign-off that Trump has withheld.
Pakistan
Pakistan
With both Prime Minister Sharif and army chief Munir simultaneously in Beijing on 25 May, Pakistan has for the first time consolidated its civilian and military mediation tracks under China's roof. Munir's direct Tehran-to-Beijing flight signals that the security and financial threads of the sequencing problem are now being worked in parallel rather than sequentially.
China
China
Beijing hosted Pakistan's principal mediators and Iran's China envoy Ghalibaf simultaneously on 25 May while its banking regulator capped new state-bank lending to five sanctioned refiners. China is simultaneously the most credible third-party underwriter of the $12bn sequencing and the state whose institutions face live OFAC secondary-sanctions exposure if the deadlock persists through GL V's expiry.
United States
United States
Trump posted on 24 May that the blockade holds until a deal is certified and signed, ruling out the informal MOU structure both sides had been building. The 'certified, and signed' condition is the first operational bar Trump has attached in 87 days, but it arrived without an executive instrument, maintaining the gap between posted ultimatum and signed US policy.