Keir Starmer has warned of a “risk of escalation” in the Middle East and beyond as a result of the US bombing of Iran, but backed the strike on Iran’s nuclear facilities and called on Tehran to return to negotiations.
The prime minister, who was quick to clarify that the UK had not been involved in the strikes, held talks with France’s president, Emmanuel Macron, and the German chancellor, Friedrich Merz, on Sunday afternoon after convening a Cobra meeting in the aftermath of the US attack.
The US made no request for any UK assistance in the bombing of the three nuclear sites, the Guardian understands, including any use of the leased Diego Garcia base in the Chagos Islands, the recent subject of a controversial deal with Mauritius.
In a joint statement, the three European leaders said it was “clear that Iran can never have a nuclear weapon and can no longer pose a threat to regional security”. They said their joint aim was to prevent Iran from acquiring a nuclear weapon and called on Tehran to address all concerns associated with the nuclear programme.
“We stand ready to contribute to that goal in coordination with all parties,” the statement said. “We urge Iran not to take any further action that could destabilise the region. We will continue our joint diplomatic efforts to defuse tensions and ensure the conflict does not intensify and spread further.”
Starmer warned earlier that the fallout from the conflict could reverberate beyond the region. “It is important that we now de-escalate the situation, stabilise the region and get the parties back around the table to negotiate,” he told broadcasters.
Flights from London to Dubai and Doha were cancelled after a British Airways flight from Heathrow to Dubai was forced to divert to Zurich on Saturday night. Israel announced on Sunday that it had closed its airspace to inbound and outbound flights.
Starmer spoke to Donald Trump on Sunday night but the official readout of the call gave no hint as to whether the prime minister had called for the US to de-escalate.
No 10 said Starmer and Trump “reiterated the grave risk posed by Iran’s nuclear programme to international security. They discussed the actions taken by the United States last night to reduce the threat and agreed that Iran must never be allowed to develop a nuclear weapon.
“They discussed the need for Iran to return to the negotiating table as soon as possible and to make progress on a lasting settlement.”
After Starmer spoke earlier on Sunday with the sultan of Oman and the king of Jordan, No 10 said the leaders agreed that “escalation of the conflict is in no one’s interests”.
The US decision to join Israel’s offensive against Iran came after western leaders, including Starmer, had urged restraint. They are due to meet again on Tuesday at the Nato summit in the Netherlands.
As recently as last Tuesday at the G7 summit, which Trump left early, Starmer said he did not have any indication the US was planning on joining the attack.
Map showing location of Iranian nuclear facilities hit by US strikes
The business secretary, Jonathan Reynolds, told Sky News that while the UK had preferred a different path, the outcome was in British interests. “We support the prevention of Iran obtaining a nuclear weapon. We had proposed a diplomatic course of action, as other European countries had done; the Iranians had rejected that.”
Reynolds said people should be in no doubt that the Iranian regime did pose a threat to the UK, but that regime change in Tehran was “not the question” when it came to these strikes. “I wanted a different way to obtain this, but I cannot pretend to you that the prevention of Iran having a nuclear weapon is anything other than [in] the interests of this country,” Reynolds told the BBC.
“This is very different to what we saw with the invasion of Iraq … I think stability for the region would come about through an agreement where Iran would acknowledge that, because of its behaviour, no country in that theatre or the wider world would be able to countenance it having nuclear weapons.”
The chair of the foreign affairs select committee, Emily Thornberry, said the strikes were a “big mistake”. She told the BBC: “The concern is it will just become a wider conflict, and we are at a very dangerous moment. The war aim is supposed to be to stop the Iranians building a bomb, but this isn’t the way to do it. At best, it can slow down the Iranians. The way to stop them building a bomb is negotiation.”
Labour and opposition MPs are likely to raise concerns in parliament when they return on Monday afternoon. The Green party co-leader, Adrian Ramsay, said: “We utterly condemn the reckless attacks on Iran by the United States that can only lead to further dangerous conflict in an already volatile region. There is no international legal basis for this unilateral action that poses a serious threat to international peace and security.”
The foreign secretary, David Lammy, had urged the US to pull back from the brink on a visit to Washington for talks with his counterpart, Marco Rubio, before attending talks with Iran on Friday alongside European allies in Geneva.
Lammy also spoke to Iran’s foreign minister, Abbas Araghchi, saying on X that he had stressed the need for de-escalation.
But Iran’s state news agency, IRNA, had a slightly different take on things, posting on X: “UK Foreign Secretary David Lammy expressed regret over the US strikes on Iran’s nuclear facilities, categorically denied any involvement, and called for continued diplomacy.”
The first part of the tweet prompted the UK Foreign Office to issue a response. A spokesperson said: “This representation of the foreign secretary’s phone call is inaccurate. The foreign secretary warned that this is a moment of extreme peril and that it is important we now de-escalate the situation, stabilise the region, and get all parties back around the table to negotiate. Iran must now immediately seek a diplomatic, negotiated solution to end this crisis.”
The Conservative leader, Kemi Badenoch, said the US strike was “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.”
Overnight, Iran launched a ballistic missile barrage against Israel in retaliation against the US action.