US President Donald Trump has said that he is seriously considering pulling the United States out of NATO, expressing frustration over what he described as a lack of support from allies for Washington’s military campaign against Iran.

In an interview with The Telegraph, Trump described the alliance as a “paper tiger” and said leaving it was “beyond reconsideration,” adding that he had long doubted its effectiveness.

The US president criticised European allies, including the UK and France, for refusing to take part in military operations in the Strait of Hormuz, arguing that support from NATO members “should be automatic.”

He drew comparisons with US backing for Ukraine, saying Washington had acted even when it was not directly involved.

“We’ve been there automatically… Ukraine wasn’t our problem… They weren’t there for us,” Trump said.

The comments underscore the widening gap between the United States and its European allies as the Iran conflict continues to test diplomatic cohesion and military coordination.

The closure of the Strait of Hormuz — a key energy route — has increased pressure on regional economies amid differences over the response to Iran’s retaliatory strikes.

US Secretary of State Marco Rubio echoed the concerns, saying Washington may need to “reexamine the value” of NATO if allies refuse to provide basing rights or operational support during US-led conflicts.

“If NATO is just about us defending Europe… but them denying us support when we need it, that’s not a very good arrangement,” Rubio said in a television interview.

British Prime Minister Keir Starmer has ruled out deploying troops for the Iran war, saying the UK would not be “dragged into” a war that is “not our war,” although London has allowed US forces to use its bases.

NATO’s collective defence clause, known as Article 5, commits members to treat an attack on one as an attack on all, but it has only been invoked once — after the September 11 attacks in the United States.

Trump’s comments come amid mounting political pressure at home and abroad, with opinion polls in the UK showing significant public opposition to the conflict and divisions over how leaders are handling relations with Washington.