Uncertainty surrounded the future of potential peace talks between the U.S. and Iran on Thursday, as tensions around the Strait of Hormuz persisted despite President Donald Trump’s announcement of an extended ceasefire earlier this week.

Tehran attacked three ships in the Strait of Hormuz on Wednesday, seizing two of them. Iranian officials said the move was in response to an American blockade of the country’s ports, as well as the recent seizure of an Iranian-flagged ship.

A day earlier, Trump announced in a social media post that a two-week ceasefire deal with Iran had been extended just hours before it was due to expire. He said the extension came at the request of Pakistan, which has served as a mediator between Washington and Tehran, adding that the truce would be in effect "until such time as" Iranian officials present a "unified proposal" for peace.

However, leaders from both sides have indicated that they stand ready to resume hostilities.

Mediators from Pakistan, Turkey and Egypt were racing to salvage peace talks between the U.S. and Iran, including arranging a potential meeting as soon as Friday, the Wall Street Journal reported, citing officials familiar with the matter.

The U.S. and Iran were exchanging messages via third parties, although little progress has been made, the WSJ said.

Speaking to Fox News on Wednesday, Trump suggested that there was "no time pressure" on staging a fresh round of talks or on the ceasefire. White House Press Secretary Karoline Leavitt also said Trump does not view Iran’s ship seizures as a violation of the pause in fighting.

A trip to Pakistan by U.S. Vice President JD Vance, who led a prior American delegation in talks with Tehran, has been put on hold. According to the Associated Press, Pakistani Interior Minister Mohsin Naqvi hoped for "positive progress" with Iran after meeting with U.S. Chargé d’Affaires Natalie Baker.

Yet Tehran has stressed that it will not participate in any negotiations as long as the American blockade is in effect, the WSJ reported.

Oil back above $100

With signs pointing to persistent oil supply disruptions through the Strait of Hormuz, a crucial shipping conduit for a fifth of the world’s oil, crude prices once again topped $100 a barrel. Brent crude futures, the global oil benchmark, were last higher by 1.8% at $103.70 a barrel.

Although oil prices have eased back from an initial spike after the start of the war in late February, they are still well above pre-conflict levels. Worries have abounded that the energy shock could trigger a spike in inflationary pressures and a slowdown in global growth.

Military planners from over 30 countries are due to continue a meeting in London later today aimed at finding a way to unblock the Strait of Hormuz, where the threat of attacks has caused tanker traffic through the narrow chokepoint to all but stop.