Keir Starmer this morning gave British backing to strikes on Iran's nuclear capabilities by Donald Trump's America.

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.

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.

Reports from the US suggested that the bombers flew direct from the US 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.

In a statement this morning Sir Keir said: 'Iran's nuclear programme is a grave threat to international security.

'Iran can never be allowed to develop a nuclear weapon and the US has taken action to alleviate that threat.

'The situation in the Middle East remains volatile and stability in the region is a priority.

'We call on Iran to return to the negotiating table and reach a diplomatic solution to end this crisis.'

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.

'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.