Nato partners have been reluctant to help reopen the strait, through which 20% of the world’s oil typically travels. Tehran has effectively closed the strait for weeks, sending global oil and gas prices spiralling while threatening a global recession.
Trump added: “Beyond not being there, it was actually hard to believe. And I didn’t do a big sale. I just said, ‘Hey’, you know, I didn’t insist too much. I just think it should be automatic.
“We’ve been there automatically, including Ukraine. Ukraine wasn’t our problem. It was a test, and we were there for them, and we would always have been there for them. They weren’t there for us.”
Singling out the UK, the US President rebuked Sir Keir Starmer for refusing to get involved in the American-Israeli war against Iran, suggesting that the Royal Navy was not up for the task.
“You don’t even have a navy. You’re too old and had aircraft carriers that didn’t work,” he said, referring to the state of Britain’s fleet of warships.
Asked whether the Prime Minister should spend more on defence, Trump added: “I’m not going to tell him what to do. He can do whatever he wants. It doesn’t matter. All Starmer wants is costly windmills that are driving your energy prices through the roof.”
After speaking to the Telegraph, the Wall Street Journal reported that Trump had raised the issue of withdrawing from Nato with White House aides.
The newspaper said he had made comments to Rubio and others in private but had made no final decision on the future of the alliance.
Following his comments, Starmer reaffirmed his support for Nato, describing it as “the single most effective military alliance the world has ever seen”.
The Prime Minister signalled that he would seek a closer relationship with Europe in response to the souring of relations with Washington and said that, “whatever the noise”, he would act in the British interest.
He said: “This is not our war, and we’re not going to get dragged into it.”
On Tuesday, the First Sea Lord admitted that the Royal Navy was not ready for war, making him the most senior serving military figure to warn of the perilous state of the armed forces.
At the start of the conflict in Iran, four of Britain’s six destroyers were out of service and under repair. The UK has been forced to borrow a warship from Germany to fulfil its Nato obligations in the North Atlantic.
The White House has grown increasingly frustrated with long-time partners over their position on the war. Marco Rubio, the Secretary of State, accused Nato of being a “one-way street” as he hit out at US allies for not allowing access to their military bases.
Speaking on Fox News in the hours before the interview with Trump, Rubio said America would have to “re-examine” its Nato membership when the war in Iran came to an end.
“I think there’s no doubt, unfortunately, after this conflict is concluded, we are going to have to re-examine that relationship.
“If Nato is just about us defending Europe if they’re attacked, but them denying us basing rights when we need them, that’s not a very good arrangement. That’s a hard one to stay engaged in.”
Trump told the Telegraph he was “glad” Rubio made the comments.
The President is set to deliver an “address to the nation” at 9pm EST on Wednesday (2pm NZT today) to provide an update on the war.
He is expected to express his disgust with Nato for what he considers the alliance’s lack of support for US objectives in Iran, according to Reuters.
He told the news agency he was “absolutely” considering an attempt to withdraw the US from the alliance. “They haven’t been friends when we needed them,” he said. “We’ve never asked them for much ... it’s a one-way street.”
On Tuesday night, he said it could end within “two weeks, maybe three”, stating that its only goal was to stop Iran from attaining nuclear weapons.
Last week, the Telegraph revealed that Trump was considering a shake-up of Nato designed to punish members that did not meet his funding demands.
British military chiefs have urged the Prime Minister to deliver the promise he made last year to boost defence spending to 3% of GDP by the end of this decade. Rachel Reeves, the Chancellor, is resisting pressure to spend billions more on defence.
Senior members of the Trump administration have pushed for a “pay-to-play model” that could block allies who fail to meet targets from decision-making, including when the bloc goes to war.
Sources close to the President said he was also considering pulling US troops out of Germany – a move that he has considered since returning to office last year.
Trump’s demand for Nato to help in his war with Iran has led to questions about Article 5, the “attack on one is an attack on all” mutual defence clause.
It has only ever been invoked once – after the 9/11 attacks on the US. More than 1100 non-US troops were killed in the subsequent war in Afghanistan, including 457 British soldiers.
The clause relates only to when a Nato member is attacked and would therefore not apply to the war in Iran, which began with joint US-Israeli air strikes on February 28.
Any decision to withdraw the US from Nato would require approval from Congress. In 2023, the country’s legislature adopted a law that prevents the President from “suspending, terminating, denouncing, or withdrawing” the United States from Nato without the consent of the Senate or an Act of Congress.
Rubio, who was a US senator at the time, co-sponsored the legislation, arguing that any decision to leave the alliance “should be rigorously debated and considered by the US Congress with the input of the American people”.
Ivo Daalder, who served as Barack Obama’s ambassador to Nato, said: “What the President can do – and there’s no question about this – he can withdraw all American troops, he can withdraw all Americans from the command structure, he can say Article 5, but don’t count on military capabilities, let alone nuclear, if you get attacked. All of that is legal.”
He said that what was described as “worst-case scenario” by some was now a reality for Europe.
“What European leader is now going to believe that the United States is going to be there as long as Trump is President?” he said.
“How many more times does Donald Trump have to say that he doesn’t like Nato for you to believe that he might not be there if there’s an armed attack on Nato?”
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