Britain was warned in advance that the US planned to hit Iran’s nuclear sites, a Cabinet minister said today as Keir Starmer gave Donald Trump’s attack the UK’s backing. 

Jonathan Reynolds said the UK had played no role in the strikes on three facilities overnight, but warned the threat of terrorism here due rise due to the close transatlantic alliance. 

And he confirmed that efforts were underway to get trapped Britons out of Israel, as Tehran launched a barrage of revenge missiles.

The Business Secretary said it would be ‘hours, not days’ before they could be evacuated, with delays so far caused by Israeli airspace being closed.

The Foreign Office has asked British nationals in Israel to register their interest in a Government-organised flight out of the country early next week. 

It came as the Prime Minister, who will chair a Cobra meeting this afternoon, said that Tehran’s atomic programme was ‘a grave threat to international security’.

US stealth bombers dropped 30,000-pound ‘bunker buster’ bombs on the Fordow nuclear facility.

Sir Keir added that the US had taken action to ‘alleviate that threat’, having previously urged Trump to use diplomacy instead, warning that military action could cause wider ramifications.

Trump last night claimed the attack using B2 steal bombers had been ‘a spectacular military success,’ something Tehran denied.

The bombers flew direct from the US rather than using the joint UK/US base at Diego Garcia in the Indian Ocean, with Mr Reynolds saying there had been no request to use it.

The Prime Minister said that Tehran’s atomic programme was ‘a grave threat to international security’ after bombers dropped 30,000-pound ‘bunker buster’ bombs on the Fordow nuclear facility.

Reports from the US suggested that the bombers flew direct from the US to attack Fordow (pictured) rather than using the joint UK/US base at Diego Garcia in the Indian Ocean

Business Secretary Jonathan Reynolds told Sky News the UK was not involved in the attacks but it was told in advance that it was happening.

He told Sky News that ‘we were informed, as you might expect, by a key ally, of this action.

‘I know people will be waking up this morning and they’ll be worried. They’ll want to know what this means,’ he added.

‘And I do want to give them reassurance that whilst the British government, the UK, has not been involved in these attacks, we have been making extensive preparations for all eventualities, including how we look after British nationals in the region and how we get them out, and the assets we have in the region to protect British infrastructure, British bases, British personnel, if we need to do that.’   

Asked about the threat from Iran-sponsored terrorism, he said: ‘It’s already at a significant level. I think it would be naïve to say that that wouldn’t potentially increase.’

As recently as Thursday Sir Keir was warning the president not to ‘ramp up’ tensions with an attack, having earlier told reporters at the G7 in Canada: ‘There is nothing the President said that suggests he’s about to get involved in this conflict.’

Opposition leader Kemi Badenoch said: ‘By targeting Iran’s nuclear sites, the US has taken decisive action against a regime that fuels global terror and directly threatens the UK. 

‘Iranian operatives have plotted murders and attacks on British soil. We should stand firmly with the US and Israel.’

The military action was also backed by Reform UK leader Nigel Farage, who tweeted: ‘Iran must not be allowed to have nuclear weapons, the future of Israel depends on it.’

The attack also saw US submarines fire 30 Tomahawk missiles at two other Iranian nuclear sites at Natanz and Isfahan.

Trump last night claimed the attack using B2 steal bombers had been ‘ a spectacular military success,’ something Tehran denied.

The attack also saw US submarines fire 30 Tomahawk missiles at two other Iranian nuclear sites at Natanz and Isfahan.

‘The strikes were a spectacular military success,’ the president claimed in a late-night address to the nation from the White House.

Trump claimed the top secret uranium enrichment base hidden deep inside a mountain at Fordow, 80 miles south of Tehran, was flattened.

Mr Reynolds told Sky News: ‘We were not and have not been involved in these attacks.’

Asked if the UK knew the attacks were about to happen, he said: ‘I can’t tell you exactly when we did know but we were informed, as you might expect, by a key ally, of this action.’

The Business Secretary said ‘no request was made’ by the US for support.

Iran’s foreign minister condemned the offensive as ‘extremely dangerous, lawless and criminal behavior.’

‘The events this morning are outrageous and will have everlasting consequences,’ Seyed Abbas Araghchi said. ‘Iran reserves all options to defend its sovereignty, interest, and people.’

This morning Israel was being struck by a barrage of missiles as Iran launched a retaliatory attack.

B-2 Stealth Bombers were used in the attack to drop bunker buster bombs