The UK has agreed to allow the United States to use British bases to launch strikes on Iranian sites targeting the Strait of Hormuz.

Prime Minister Sir Keir Starmer previously allowed US forces to use the bases only for defensive operations to prevent Iran firing missiles that put British interests or lives at risk.

On Friday, Downing Street said ministers approved an expansion of the targets to help protect ships in the strait – a vital oil shipping channel - and still on the basis of "collective self-defence".

US President Donald Trump said the UK "should have acted a lot faster", while Iran's foreign minister Seyyed Abbas Araghchi claimed Sir Keir was "putting British lives in danger".

The UK will still not be directly involved in the strikes and Downing Street said "the principles behind the UK's approach to the conflict remain the same".

Conservative Party leader Kemi Badenoch said the decision was the "mother of all U-turns" in a post on social media site X.

Liberal Democrat foreign affairs spokesman Calum Miller said the government's decision showed the UK was "being drawn further and further down Trump's slippery slope".

He called on Sir Keir to allow Parliament to vote on the terms of the agreement with the US for their use of UK bases.

Green Party leader Zack Polanski said it was "another worrying escalation" and said MPs "must be given a vote on our involvement".

The UK bases used by the US have been RAF Fairford in Gloucestershire and Diego Garcia in the Indian Ocean.

Speaking to reporters, Trump said of the UK's decision: "It's been a very late response from the UK.

"Surprised because the relationship is so good but this has never happened before. They were really pretty much our first ally all over the world."

The US president earlier called Nato allies "cowards" for refusing to offer warships to reopen the shipping channel, and claimed reopening the strait would be a "simple" military task with "little risk".

UK military planners have joined the US Central Command to look at options for getting tankers through the strait, which has been effectively closed off by the threat of Iranian attacks in retaliation for the US-Israeli bombing campaign.

Just under 100 ships have passed through the strait since the start of March, according to data analysed by BBC Verify.

Before the war, about 138 ships passed through the strait each day, carrying one fifth of the global oil supply, according to the Joint Maritime Information Centre.

A Downing Street spokesperson said of Friday's discussions by ministers: "They agreed that Iran's reckless strikes, including on Red Ensign vessels and those of our close allies and Gulf partners, risked pushing the region further into crisis and worsening the economic impact being felt in the UK and around the world.

"They confirmed that the agreement for the US to use UK bases in the collective self-defence of the region includes US defensive operations to degrade the missile sites and capabilities being used to attack ships in the Strait of Hormuz."

Downing Street added ministers want "urgent de-escalation and a swift resolution to the war".

The expansion comes after Iran's foreign minister warned the UK it views its choice to let the US use British bases as "participation in aggression".

In his account of the call with UK Foreign Secretary Yvette Cooper, Araghchi said he had also criticised the "negative and biased" approach of the UK and demanded that it cease any co-operation with the United States.

The Foreign Office said Cooper had condemned Iran's "reckless attacks" and its "disruption and closure of the Strait of Hormuz".

A spokesperson said she had also called for "an immediate comprehensive moratorium on all attacks on civilian infrastructure, including oil and gas installations".

Araghchi later wrote on X: "Ignoring his own people, Mr Starmer is putting British lives in danger by allowing UK bases to be used for aggression against Iran.

"Iran will exercise its right to self-defence." (BBC, excluding headline)

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