Estimates of how much crude moves through the Strait of Hormuz now differ by a factor of more than four. Tankertrackers puts flows at 3.7 million barrels a day, Bloomberg at 6 to 8 million, and figures implied by US military claims at 16.4 million. Seven months into the US-Iran war, that gap matters because the market has barely moved on either side of the diplomacy: Brent fell 2.1% when the Iranian offer was reported on September 25 and rose 0.9% on September 28 when Washington rejected its terms.
One Offer, Two Sequences
Iran offered, in a proposal reported September 25, to reopen the strait within seven days if the United States eases pressure, including steps toward ending its military blockade of Iranian ports and halting military operations in the strait. The secretary of Iran Supreme National Security Council outlined seven conditions, among them the end of the blockade and the release of frozen Iranian assets. The offer also included a restart of nuclear talks.
The disagreement is about order. Under the Iranian plan, sanctions relief comes first and the strait opens on the seventh day. Washington insists on a different sequence and rejected the plan, and indirect talks resumed through Qatari mediators on September 28.
Brent rose 23.8% from 87.84 dollars on August 26 to 108.75 on September 15, and has since eased 4.8% to 103.53 on September 30, with the offer and its rejection moving the settlement by only 2.1% and 0.9% on the two days. Brent futures traded above 107 dollars intraday on September 28, according to CNBC, before settling at 105.28.
Event markers show the dates on which the Iranian reopening proposal was reported and the United States rejected its terms. The series shows the front-month contract and ends with the September 30 settlement; the contract rolls at expiry.
Counting Ships and Barrels
The flow estimates diverge because the traffic is hard to observe. Kpler recorded a 10-day average of 13 vessel transits a day at the end of August, against a pre-war baseline of around 100 ships a day. Another tracker counted 25 transits on September 27, 13 on September 26 and 6 on September 25, against a baseline of about 130. On September 27, 14 of the 25 vessels were operating without transponders, so more than half of the day count was visible only through indirect tracking.
The day-to-day swings in the counts are large relative to the totals, which means a single reading says little about direction. The estimates also come from different sources with different methods, and none of them is an audited measure of cargo.
The Bypass and the Fuel Gap
Saudi Arabia restarted its East-West pipeline, which was running at about 3.5 million barrels a day as of September 28, roughly half capacity, with loadings at Yanbu on the Red Sea resumed at about half of pre-attack rates despite continued Houthi targeting. That route reduces the shortfall without removing it.
Refined fuel is tighter than crude. PetroChina has reportedly withdrawn several gasoline and jet fuel cargoes scheduled for October as Beijing preserves domestic inventories, which limits the supply of refined products even as crude flows recover. The energy channel is already visible in Canadian consumer prices, where gasoline was 22.8% higher in August than a year earlier, according to Statistics Canada.
What Would Change the Picture
The sequencing dispute is the variable to watch. A compromise on order, with some relief and some reopening in the same window, would be the first observable change, and the muted reaction to both the offer and its rejection suggests the market has placed little weight on either arriving soon. Until then, prices are set by tanker counts that disagree, by the Saudi bypass rebuilding toward its pre-attack rate, and by headlines on the talks.