David Lammy has signalled a dramatic hardening of the government’s position on the war on Iran, warning Royal Air Force jets could legally strike Iranian missile sites to prevent attacks on British interests in the Middle East.
The deputy prime minister’s comments sparked chaos as No10 scrambled to deny accusations of a U-turn and warnings the government risked sliding down a “slippery slope”.
Sir Keir Starmer initially barred the use of UK bases in the operation. But on Sunday he dramatically changed his mind and gave America permission for the “limited, specific defensive purpose” of protecting UK and US allies, as Iran continued to lash out.
Mr Lammy said UK aircraft were currently only shooting down missiles and drones fired by Iran. But he said it would be legal for them to go further and strike the Iranian bases being used to launch attacks.
The justice secretary’s comments came as he embarked on a shambolic media round where he incorrectly said that Cyprus was part of Nato. He also referred to the deployment of RAF “Tycooons” in the region rather than Typhoons.
The defence secretary John Healey has not ruled out UK aircraft taking part in strikes on Iran, saying that "as circumstances in any conflict change, you've got to be willing to adapt the action you take".
Downing Street said it remained the UK's intention to focus on defending allies in the Middle East while allowing the US to strike targets in Iran.
The prime minister's official spokesman said: "We have consistently said that we'll take the necessary steps to prevent future strikes ... (that) as we've set out over the course of the week is allowing the US to take out those missiles at source whilst we are defending the skies. And that is a consistent position that we have conveyed throughout the week."
Tory leader Kemi Badenoch accused the government of a “U-turn” and backed the idea of RAF jets striking Iranian missile sites.

"You can't always wait for people to attack you. Sometimes you have to make sure that you get there first to stop their ability to hurt your citizens," she told the BBC.
The Liberal Democrats called for urgent clarification on Mr Lammy’s remarks, and said any “offensive” action would require a Parliamentary vote.
On Thursday, Sir Keir Starmer announced that an additional four British Typhoon fighter jets are being deployed to Qatar to strengthen “defensive operations” in the region.
When asked whether such operations could include hitting targets within Iran to prevent the launch of attacks, Mr Lammy said he believed this “would be lawful”.
“It is entirely legal to protect our people and protect our staff, and therefore all operational capability is available to us in those circumstances,” he told BBC Breakfast.
Asked if that meant the UK could attack Iranian missile sites from our bases, he said: “I’m not here to act as a lawyer, but I think your viewers will understand that in response to being attacked, yes, we can take down sites that are anticipating attacking our people across the region.”
Asked if the UK could fire at an Iranian base in anticipation of it launching an attack, he said: “It is my understanding that that would be legal.”
The first government-chartered plane evacuating British nationals from the region touched down in the UK in the early hours of Friday morning, as the US-Israeli war with Iran entered its seventh day.
Sir Keir’s announcement that he would send more fighter jets to the Middle East came amid mounting criticism of the British response to the conflict.
The prime minister was forced to reject criticism from opponents and allies that Britain had not acted fast enough when fighting began, and said he “stands by” his decision not to join the initial strikes on Tehran over the weekend.

The UK has been criticised for failing to have air defence measures in place to sufficiently protect RAF Akrotiri in Cyprus, which was hit by a drone.
Mr Lammy also insisted he was not embarrassed by the UK’s response to the Middle East crisis, amid concerns that air defence destroyer HMS Dragon is not expected to sail to the eastern Mediterranean until next week.
Asked if he was embarrassed, Mr Lammy told Sky News: “Absolutely not…. we have F-35s, Typhoons in the sky taking down missiles as we speak and that has happened over Jordan, it’s happened over Qatar and of course, we will support nationals in the region.
“It’s also right to say that we coordinate with allies, the French, the Germans. Cyprus is a Nato ally, so we coordinate also with other teams and other close allies on how we equip the area.
“HMS Dragon will be in the region in the coming weeks to further bolster and further support our air defences.”
The US and Israel have continued to batter Iran with nationwide strikes, and in turn, Iran has kept up retaliatory strikes on Israel and US bases and across the region.
The conflict has led to thousands of Britons leaving the region, with some 4,000 returning on commercial flights before the first government charter plane landed at London Stansted shortly before 1am Friday.
Mr Lammy said on Friday that some 6,500 British nationals have returned from the UAE and that 100,000 British nationals registered their presence in the region.
He said the UK government is intending to see more charter flights out of Oman and told the BBC: “This is a technical operation, and we've got more people to evacuate than in Afghanistan... this is a pretty big feat.”
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