US-Iran MOU Unlocks Strait of Hormuz, Oil Tanker Traffic Surges 105% After Deal

The implementation of a newly signed memorandum of understanding between the United States and Iran has effectively unlocked the Strait of Hormuz, clearing a massive backlog of stranded vessels and restoring the flow of global energy supplies. The diplomatic agreement, which establishes a framework for safe passage and eases the US naval blockade, triggered an immediate 105% day-on-day surge in commercial tanker traffic through the critical maritime chokepoint.[3][4]

On Wednesday alone, approximately 60 commercial vessels transited the strait, marking a stark reversal from the near-standstill that paralyzed the waterway during the peak of the conflict in 2026. These ships transported an estimated 22 million barrels of oil out of the Persian Gulf in a single 24-hour window, providing massive relief to a constrained global market.[1]

A US official, speaking on condition of anonymity, confirmed the transit data, stating that the vessels were "carrying the highest daily volume of crude oil since early July." The rapid recovery in transit volumes underscores the market's reliance on the US-Iran interim accord, which has provided shipping operators with the short-term confidence needed to resume operations.[1]

To mitigate the lingering risks, about 40 of the vessels that crossed the strait coordinated their movements with the US military. This escort architecture serves a dual purpose: reassuring freight markets that the chokepoint remains open, and signaling to Tehran that Washington is actively enforcing the terms of the memorandum.[1]

Before the outbreak of hostilities in late February, the Strait of Hormuz typically handled about 125 large commercial vessels daily, accounting for roughly one-fifth of the world's seaborne crude oil and liquefied natural gas. The recent surge brings traffic closer to those pre-war baselines, though the recovery remains fragile and heavily dependent on the ongoing diplomatic negotiations.[1][4]

Despite the surge in successful transits, the reality on the water remains precarious. Iran's Islamic Revolutionary Guard Corps (IRGC) continues to exert pressure on commercial shipping, insisting that all vessels must use Tehran-approved routes in the northern section of the waterway and coordinate directly with Iranian authorities.[2][5]

This tension materialized on September 21, when the IRGC struck another commercial tanker, demonstrating that the diplomatic agreement has not entirely eliminated the physical risks to mariners. The attack targeted a vessel navigating an alternative southern route near the Omani coastline, a corridor that shipping operators have increasingly utilized to avoid Iranian coastal batteries.[2][5]

The dispute over authorized transit lanes highlights a fundamental divergence in how Washington and Tehran interpret the MOU. While the US asserts that the strait is fully open for international navigation across all established lanes, Iran maintains that the agreement requires vessels to acknowledge its administrative control over the waterway.[2][4]

For global energy markets, the stakes of this fragile truce are immense. The resumption of steady tanker traffic has already begun to bleed the geopolitical risk premium out of crude oil futures, but insurers and shipping firms remain cautious. Until a permanent maritime arrangement is finalized, the Strait of Hormuz will continue to operate in a tense limbo, balancing the immediate relief of restored oil flows against the looming threat of renewed escalation.[1][2][4]