The IRGC says the aggression came in response to what it described as the US seizure of an Iranian commercial vessel.

An Iranian gunboat has fired on a container vessel near the coast of Oman, according to a British maritime monitoring agency, in an incident that occurred hours after United States President Donald Trump said he would extend a ceasefire with Iran.

The United Kingdom Maritime Trade Operations (UKMTO) centre said on Wednesday that the ship’s captain reported that the vessel had been approached by a vessel of Iran’s Islamic Revolutionary Guard Corps (IRGC) before shots were fired.

It “has caused heavy damage to the bridge. No fires or environmental impact reported,” the agency added. No casualties were reported, and all crew members were said to be safe.

British maritime security firm Vanguard Tech said the ship was sailing under a Liberian flag and had been informed it had permission to pass through the Strait of Hormuz, one of the world’s most strategically important waterways.

Iranian news agency Tasnim, however, said the vessel had ignored warnings issued by Iran’s armed forces.

The incident followed a warning from the IRGC’s Khatam al-Anbiya Central Headquarters after what it described as the US seizure of an Iranian commercial ship in the Sea of Oman, the IRNA news agency reported.

It accused Washington of violating the ceasefire and carrying out “armed piracy” after allegedly firing on the Iranian vessel and disabling its navigation systems.

Trump extends ceasefire

Trump earlier announced he would delay a planned military attack on Iran after requests from Pakistan’s army chief Asim Munir and Prime Minister Shehbaz Sharif.

Writing on Truth Social, Trump said the decision was made because Iran’s government was “seriously fractured” and needed time to present a unified position.

“We have been asked to hold our Attack on the Country of Iran until such time as their leaders and representatives can come up with a unified proposal,” he wrote.

He added, however, that the US naval blockade of the Strait of Hormuz would remain in place and said the military had been ordered to stay “ready and able”.

The announcement marked a shift from comments made a day earlier, when Trump said it was “highly unlikely” he would extend the truce beyond Tuesday.

‘Positive and negative signals’ from Tehran

Al Jazeera’s Tohid Asadi, reporting from Tehran, said Iranian officials were sending mixed messages over the ceasefire and the prospects for negotiations.

“Tehran is saying they won’t negotiate under imposed terms and conditions … when we compare the initial 10-point and 15-point proposals by the Iranians and Americans, we can understand that the two sides are poles apart,” he said.

“The atmosphere is also clouded by this mistrust in Tehran towards the United States, as well as the simultaneous military rhetoric related to a potential failed negotiation … It is a warning that another round of confrontation may be ahead.”

He said Iran still viewed the Strait of Hormuz as a key source of leverage in any talks.

“It’s trying to exercise authority over the ships and vessels transiting this strategically significant chokepoint,” he said.

Asadi added that Iranian officials framed their regional position as based on mutual security. “Iranians are saying that the basis of their foreign policy behaviour, particularly when it comes to Israel, is security for all versus security for none,” he said.