President Donald Trump declared on Wednesday that the United States would destroy one Iranian bridge or power plant, including those in or near Tehran, for every future attack on a vessel in the Strait of Hormuz. The statement, posted on his Truth Social platform, specified that the retaliation would apply regardless of whether Iran used missiles, rockets, drones or other weapons. The threat came as the US military conducted an eleventh consecutive night of air strikes against what it described as Iranian military command centres, maritime assets and drone infrastructure, aimed at degrading Tehran’s ability to threaten commercial shipping.

Viewed from Washington, the move is presented as a calibrated deterrent to force the reopening of the strategic waterway, through which one-fifth of globally traded oil and gas passed in peacetime before the conflict. Secretary of State Marco Rubio, speaking at a Southeast Asian ministers’ meeting in Manila, said the US remained open to a negotiated settlement but accused Iran of failing to honour commitments made under a preliminary ceasefire that collapsed in June. The Pentagon has put the cost of the war at $37.5 billion, with 18 American service members killed, and the White House faces domestic pressure ahead of midterm elections as gasoline prices rise.

Iranian state media reported that air defences were activated over Tehran and explosions were heard in several provinces, including near the Bushehr nuclear power plant. The Islamic Revolutionary Guard Corps claimed responsibility for drone and missile attacks on US bases in Jordan, Kuwait and Bahrain, and the foreign ministry in Tehran insisted that diplomatic exchanges with Washington through mediators were continuing. Iranian officials have separately rejected as a “fabricated pretext” US allegations of an undeclared nuclear enrichment site at Kolang mountain, near Natanz, which Trump identified as a potential target. International legal experts, cited by multiple outlets, have warned that strikes on civilian infrastructure could constitute war crimes under international humanitarian law.

The conflict, which began in late February with US and Israeli strikes that regional media say killed Iran’s supreme leader, has increasingly centred on control of the Strait of Hormuz. Iran has fired on commercial vessels it says failed to coordinate with its authorities, while the US has reimposed a naval blockade on Iranian ports. The Iran-aligned Houthi movement in Yemen has separately threatened Saudi shipping in the Red Sea, placing a second major trade chokepoint at risk. Benchmark Brent crude rose to around $94 a barrel. Diplomatic efforts, including a recent Pakistani mediation initiative, have yet to yield a new ceasefire, and the US military command indicated that operations would continue.