Middle East crisis live: Iran warns US blockade of strait of Hormuz would violate ceasefire

Reports indicate that the reopening of the strait was one of the major sticking points in the weekend negotiations between the US and Iran. Tehran has indicated it would like to retain control of the waterway after the war has finished, and has floated a plan to charge a fee of up to $2m a ship to transit through the waterway. Donald Trump and other world leaders have rejected such a plan as an attack on “freedom of navigation”.

Despite the US president’s claims that reopening the waterway is not his responsibility, he is under pressure to resolve the issue before the continued closure of the strait unleashes an even greater crisis for the global economy.

If Trump’s strategy succeeds, he will eliminate Iran’s greatest point of leverage in negotiations and clear the strait again for global trade, potentially lowering oil prices.

The US military has not offered many details yet, including how many warships will enforce it, whether warplanes will be used and whether any Gulf allies will assist in the effort.

Experts say it’s unlikely the US military will fire missiles or other weapons at vessels, given the risk of an environmental disaster. The most likely option is the US navy will try to force them to change course through threats – and if that doesn’t work, they will launch armed boarding parties to take physical control of the ships, experts say.

“Trump wants a quick fix,” says Dana Stroul, a former senior Pentagon official during the Biden administration and now at the Washington Institute for Near East Policy.

The reality is, this mission is difficult to execute alone and likely unsustainable over the medium to long-term.”

Donald Trump’s threatened blockade could boost oil prices by $5 to $10 a barrel, estimates Michael Lynch, a distinguished fellow at the Energy Policy Research Foundation.

The blockade would take an estimated 2m barrels of oil per day off the market, and the Iran war had already taken roughly 10m barrels a day out of supply, Lynch said.

This is a pretty big insult to a pretty big injury, I guess, is the way to put it.”

But Lynch said the blockade might be short-lived as Trump would be pressured to walk it back.

I wouldn’t be surprised to see him to give it up by midweek, especially if oil prices keep going up.”

Brent crude oil – the international standard – has gone from roughly $70 a barrel before the war in late February to more than $119 at times.

Lloyd’s List Intelligence have said that “all traffic” through the strait of Hormuz stopped after President Donald Trump announced on Truth Social that the US would blockade the waterway. It said two vessels that were leaving the strait turned around after the post.

A trickle of traffic had returned to the strait in the days since the US and Iran agreed to pause the conflict. Three supertankers fully laden with oil passed through the strait on Saturday, shipping data showed. In normal times up to 140 vessels transit through the waterway.

Donald Trump has said he doesn’t care if Iran comes back to negotiations with the US after the weekend talks in Pakistan ended without a deal.

“I don’t care if they come back or not,” Trump was quoted as telling reporters on Sunday at Joint Base Andrews military base in Maryland on his return from Florida.

If they don’t come back, I’m fine.”

More here on Donald Trump tearing into Pope Leo XIV, branding him “weak on crime and terrible for foreign policy” and claiming he is hurting the Catholic church.

The US president also posted on his Truth Social platform that it was only because he was president that the US-born Leo became pope.

I like his brother Louis much better than I like him, because Louis is all MAGA. He gets it, and Leo doesn’t!

Trump also said in his post:

Unfortunately, Leo’s Weak on Crime, Weak on Nuclear Weapons, does not sit well with me…

Leo should get his act together as Pope, use Common Sense, stop catering to the Radical Left, and focus on being a Great Pope, not a Politician. It’s hurting him very badly and, more importantly, it’s hurting the Catholic Church!

Trump’s attack came after the pontiff denounced a “delusion of omnipotence” as fuelling the US-Israel war in Iran and demanded political leaders stop and negotiate peace.

Leo also presided over an evening prayer service in St Peter’s Basilica on Saturday as the US-Iran talks began in Pakistan amid the fragile ceasefire, the Associated Press reports

The pope didn’t mention the US or Trump by name in his prayer but the pontiff’s tone and message appeared directed at Trump and US officials, who have boasted of US military superiority and justified the war in religious terms.

Trump spoke to reporters in Maryland soon after his social media post and said: “I don’t think he’s doing a very good job,” adding that “I’m not a fan of Pope Leo”.

Welcome to the Guardian’s continuing coverage of the US-Israel war on Iran and its consequences for the wider region, the world and the global economy.

Here are the main developments:

• Trump said the US Navy would start blockading the Hormuz strait and would also interdict every vessel in international waters that had paid a toll to Iran. In a lengthy post on his Truth Social platform, the president said the US was going to start “BLOCKADING any and all Ships trying to enter, or leave, the Strait of Hormuz”.

• In another post Trump also claimed Iran had “knowingly failed” to make good on its promise to open the strait, causing “anxiety” and “pain” for many countries around the world.

• US Central Command (Centcom) announced it would begin its blockade of the strait beginning Monday morning. “Centcom forces will begin implementing a blockade of all maritime traffic entering and exiting Iranian ports on April 13 at 10am ET [1400 GMT], in accordance with the president’s proclamation.”

• Iran’s Revolutionary Guard warned that “approaching military vessels to the strait of Hormuz is considered a violation of the ceasefire”.

• Oil prices rose in early market trading after Trump’s blockade announcement. The price of US crude oil rose 8% to $104.24 a barrel and Brent crude oil – the international standard – rose 7% to $102.29. Australia’s share market dropped sharply on Monday morning.

• Donald Trump and his advisers are looking at resuming limited military strikes in Iran in addition to the US blockade of the strait of Hormuz, the Wall Street Journal is reporting, citing officials and people familiar with the situation.

• Trump launched a scathing attack on Pope Leo XIV, saying he was “weak on crime and terrible for foreign policy” and was hurting the Catholic church. “Leo should get his act together as Pope,” the president said on Truth Social. The attack came after Leo denounced the “delusion of omnipotence” as fuelling the US-Israel war in Iran and demanded political leaders stop and negotiate peace.

• Australian prime minister Anthony Albanese said his government had not been asked to participate in any US blockade of the strait of Hormuz and that he wanted to see negotiations between the US and Iran continue.

• Trump reiterated his threat to destroy Iran’s power plants and other civilian energy infrastructure if no deal was reached to end the war, which he started with Israel in what is widely seen as an illegal and unprovoked attack. “I could take out Iran in one day,” he told Fox News on Sunday.

• Trump also said the US didn’t need the strait. “We don’t get our oil from there. We have so much oil,” he told Fox. “We have boats pouring up to the United States … We don’t need the strait.”

• Iranian parliamentary speaker Mohammad Bagher Ghalibaf, who led the Tehran side in the US talks, said Trump’s new threats would have no effect on the Iranian nation. “If you fight, we will fight, and if you come forward with logic, we will deal with logic. We will not bow to any threats.” He later taunted Trump on X, posting: “Enjoy the current pump figures. With the so-called ‘blockade’, Soon you’ll be nostalgic for $4–$5 gas.”