Tanker movements through the Strait of Hormuz have dropped sharply as the US-Iran standoff shows no clear sign of ending, raising fresh concerns that prolonged restrictions could eventually trigger a physical oil supply squeeze.
Only five tanker crossings were recorded on Wednesday and nine on Thursday, according to Kpler data cited by Reuters, compared with a monthly average of 12 crossings.
The latest figures underline the growing strain on one of the world’s most important oil transit routes, even as crude prices have so far remained relatively restrained by a sharp build-up in US inventories.
Five tankers entered the waterway on Thursday while four exited, with most of the vessels using the Iranian side of the strait.
The slowdown comes as Washington signals that its confrontation with Tehran could persist. US Defence Secretary Pete Hegseth said the US Navy could maintain its blockade of Iran indefinitely by rotating ships in and out of the region.
He also warned that Washington would introduce additional measures against Iran, describing them as potentially unprecedented in the history of economic isolation.
The tougher US stance suggests that the dispute over control and access to the Strait of Hormuz remains unresolved, despite diplomatic efforts aimed at easing tensions.
For oil traders, however, the immediate focus has shifted towards supply data from the United States.
US commercial crude inventories jumped by more than 17.4 million barrels last week, providing a major bearish signal and helping to offset concerns created by the disruption in Hormuz.
That inventory build has so far prevented the physical supply risks from translating fully into crude prices.
The underlying supply picture remains less comfortable. Global inventories are being depleted, including as countries draw down strategic reserves to cushion the market against disruptions.
China is also returning to the crude market after unusually weak imports in May and June. Increased Chinese buying could add further pressure to available supplies if Hormuz traffic remains restricted.
Analysts warn that the combination could become critical if the standoff lasts for several more weeks. Continued restrictions on tanker movements could eventually push the physical market beyond a tipping point, when shortages become visible and crude prices respond sharply.
The shipping disruption is not mirrored to the same extent through the Bab el-Mandeb Strait, where Kpler recorded 19 commodity carriers passing on Thursday.
However, the Hormuz figures provide a clearer indication of the pressure building around Middle East oil flows. Kpler's data only captures vessels with their transponders switched on, meaning the actual number of movements could be higher.
With Washington threatening to prolong its blockade and tanker traffic through Hormuz remaining below its monthly average, the market is increasingly watching whether the disruption becomes a temporary shipping constraint or develops into a sustained physical crude shortage.