Trump vows blockade as Strait of Hormuz crisis rattles energy markets

Trump said he would reinstate a blockade of Iranian ships in the Strait of Hormuz as the narrow waterway again became a pressure point for oil prices, shipping insurance and global supply chains. The International Maritime Organization is monitoring the crisis to protect more than 20,000 seafarers in the region, including crews stranded on vessels that could not get out.

Arsenio Dominguez, the IMO secretary-general, said there was “no commercial justification” for risking seafarers’ lives and urged maximum restraint.

An average of 20 million barrels a day of crude oil and oil products passed through the Strait of Hormuz in 2025, the International Energy Agency said. The strait was only 29 nautical miles wide at its narrowest point, with two-mile-wide channels for inbound and outbound shipping. The U.S. Energy Information Administration put the strait’s 2024 average at about 20 million barrels a day, roughly 20% of global petroleum liquids consumption, and said very few alternative export routes exist if it is closed.

Attacks on July 7 involving a Qatari LNG tanker and a Saudi crude tanker near the strait pushed maritime threat levels to severe and sent oil prices higher. Renewed hostilities on July 9 left about 6,000 seafarers stranded aboard hundreds of vessels, the United Nations said.

Shipping traffic through Hormuz increased after a June 18 memorandum of understanding between the United States and Iran to reopen the waterway, the EIA said, and it expected global oil production and trade flows to return to near pre-conflict levels by the end of 2026, with most shut-in production restored by early 2027. Before that, it estimated that Iraq, Saudi Arabia, Kuwait, the United Arab Emirates, Qatar and Bahrain collectively shut in 7.5 million barrels a day of crude production in March because of the disruption.

Iran's joint military command told oil tankers moving through the strait to use approved routes or face a forceful response, even after Trump declared the strait open and toll-free.