Commercial ships anchor off the coast of the United Arab Emirates due to navigation disruptions in the Strait of Hormuz, Dubai.

• Iran insisted that it would not open the Strait of Hormuz as long as the US naval blockade remained in place.
• The US military ordered 31 vessels to turn around or return to port.
• US President Donald Trump said he would maintain the truce to allow more time for peace talks.

Iran’s vow not to reopen the Strait of Hormuz - so long as a US naval blockade remained in place - was held into Thursday despite a ceasefire extension, as the Gulf nation announced the seizure of two ships trying to cross the strategic waterway.

US Central Command (CENTCOM) said late on Wednesday that it had also “directed 31 vessels to turn around or return to port” as part of its own “blockade against Iran”.

As the clock ticked for a return to the war that has engulfed the region, US President Donald Trump had said on Tuesday he would maintain the truce to allow more time for Pakistani-brokered peace talks.

Iran said it welcomed the efforts by Pakistan, but made no other comment on Trump’s announcement.

“A complete ceasefire only has meaning if it is not violated through a naval blockade,” said Iranian parliament speaker Mohammad Bagher Ghalibaf, who led Tehran’s delegation in the first round of talks in Islamabad.

“Reopening the Strait of Hormuz is not possible amid a blatant violation of the ceasefire.”

READ | Trump extends Iran war ceasefire at request of mediator Pakistan, but keeps ports closed

Oil prices jumped 4% before easing on Thursday after Iran vowed not to reopen the Strait of Hormuz so long as a US blockade remained in place.

At around 00:25 GMT, the benchmark US oil contract West Texas Intermediate (WTI) climbed 4.06% to $96.73 per barrel.

International oil benchmark Brent North Sea crude rose 3.62% to $105.63.

Both eased back in the following minutes.

Trump had said he wanted to give time for Iran’s “fractured” leadership to come up with a proposal, in what many observers saw as a face-saving way to avoid renewed war.

Trump told the New York Post that talks could resume in Pakistan within two to three days, even though Iran has not confirmed participation and Vice President JD Vance put his travel to Islamabad on hold Tuesday.

Trump also claimed that Iran, at his request, had halted alleged plans to execute eight women arrested over massive anti-government protests in the weeks before the attack.

But Iran’s judiciary described his remarks as “false news”, saying the women had never faced the death penalty.

Iran’s elite Revolutionary Guards said they forced two ships to the Iranian shore from the Strait of Hormuz, the narrow gateway for about one-fifth of the world’s oil.

“The Islamic Revolutionary Guard Corps naval force this morning identified and stopped in the Strait of Hormuz two violating ships,” the Guards said in a statement.

They identified the vessels as the Panama-flagged container ship MSC Francesca and the Liberia-flagged Epaminondas.

Panama’s foreign ministry confirmed the seizure of the MSC Francesca, calling it a “serious attack on maritime security” and an “unnecessary escalation”.

UK-based maritime security monitors confirmed that three commercial vessels had reported incidents involving gunboats in the strait.

Among them, a container ship reported being fired upon by a Revolutionary Guards boat 15 nautical miles northeast of Oman, causing damage to the bridge but no casualties, monitor UKMTO said.

Under orders from Trump, the US Navy is attempting to block vessels heading to or from Iranian ports, seeking to ramp up pressure on the Iranian economy even without all-out war.

Iran, in retaliation for being attacked, has said that vessels must seek permission to leave or enter the Gulf through the strait.

It had earlier promised free passage during the ceasefire, but returned to defiance after Trump announced the blockade.

The US Defence Department said on Tuesday that US forces had intercepted and boarded a “stateless sanctioned” vessel.

AFP has identified the ship as one linked to Iranian activity. Both sides accuse the other of ceasefire breaches.