Oil Prices Rise as U.S.-Iran Tensions Grip Strait of Hormuz

Oil prices extended their gains Monday as escalating U.S.-Iran tensions over the Strait of Hormuz fueled concerns about global energy supplies and shipping disruptions.

Brent crude futures for October delivery rose 2.5% to $90.68 per barrel, while U.S. West Texas Intermediate (WTI) crude gained 2.7% to $83.64. Brent had climbed nearly 6% the previous week, with WTI advancing more than 5.5%.

President Donald Trump again claimed the United States has “total control” of the Strait of Hormuz, pointing to Washington’s naval blockade of Iranian ports. Iran has separately asserted control over the strategic waterway and demanded conditions including an end to hostilities and the unfreezing of Iranian assets before fully reopening the route.

Monday also marked the expiration of a U.S.-Iran memorandum of understanding signed in June. Trump indicated he was not seeking an extension.

Shipping activity through the Strait of Hormuz remains sharply constrained. Kpler data showed only three confirmed vessel crossings on Sunday, while total crossings fell 19.5% to 95 last week. Before the conflict, more than 130 ships reportedly passed through the strait each day.

Meanwhile, Iran has been working with Oman on a potential framework for managing the waterway. Trump threatened military action against Oman if it interfered with U.S. objectives, adding further uncertainty to negotiations.

ANZ analysts said refined petroleum products, particularly diesel, face even greater pressure than crude oil. Gulf refinery disruptions, shipping constraints and strong global demand have tightened diesel supplies. Ukrainian attacks on Russian oil infrastructure are adding to concerns that petroleum markets could become tighter in the coming months.

Supply risks have overshadowed weaker oil demand projections after both OPEC and the International Energy Agency lowered their 2026 forecasts.

U.S. energy security is also drawing attention. Department of Energy data showed the Strategic Petroleum Reserve fell by 5.3 million barrels in the week ending August 14 to 293.4 million barrels, its lowest level since 1982. The decline comes amid coordinated emergency oil releases aimed at limiting energy price increases.