Sir Keir Starmer admits he would push nuclear button as prime minister if UK was under attack

In an exclusive interview with ITV News, the Labour leader told Political Correspondent Harry Horton a nuclear deterrence 'only works if there is a preparedness to use it'.

Words by Elisa Menendez, Westminster Producer

Sir Keir Starmer has said he would be willing to push the nuclear button if Britain was under attack, should he be elected in as prime minister.

In an exclusive interview with ITV News, the Labour Party leader said a nuclear deterrence "only works if there is a preparedness to use it".

In a dramatic shift from his predecessor Jeremy Corbyn, whose ambition was to see a nuclear-free world, and some Labour frontbenchers who previously voted to scrap Trident, Sir Keir today outlined plans to use the UK's nuclear deterrent as the "bedrock" of his plans to keep Britain safe.

Sir Keir also announced he would be willing to ramp up defence spending to 2.5% of GDP when the economy allows, and focus on increasing jobs and skills in the sector.

The leader of the opposition said "the only way to have a safer world is to have an effective [nuclear] deterrent", adding: "It's the single most important part of our armoury to protect our country, and that's why I'm so committed to it.

"It's important that we see this as a long-term project because not only do we need the deterrence today, but we need the upgrades and the continued deterrence as we go forward.

"I do want a safer world, but it is important to appreciate that deterrence and safety go together. They're two sides of the same coin."

When pressed on whether he would be willing to press the red button if he ever became prime minister, even if it meant potentially killing millions, he repeated that the deterrence only works if there's a "preparedness to use it", adding: "Everybody understands that... So, that is a clear answer to your question."

Watch the wide-ranging interview in full:

Questioned on the heavy burden that would come with the decision and how he would assess if he'd be prepared to make it, Sir Keir replied: "The first duty of any government and of any prime minister is defence of the realm, defence of the country... So that would be my responsibility, were I privileged enough to be elected in to serve our country."

Elsewhere in the interview, Sir Keir refused to say three times whether Angela Rayner should quit if she is found to have broken the law over the 2015 sale of her council house in Stockport, which Greater Manchester Police is investigating.

The Labour leader said he welcomes the police investigation and that it will allow a “line to be drawn” on the issue.

"I have full confidence in Angela Rayner and that she hasn't broken the rules. She will cooperate with the investigation, as you would expect. It is now a matter for the police," he said.

Ms Rayner previously said she did "nothing wrong" when selling her former council house before she became an MP - following questions about whether she paid the right amount of tax on the sale.

The new probe comes after James Daly, deputy chairman of the Conservative Party, made police aware of neighbours contradicting Ms Rayner's statement that a property, separate from her husband's, was her main residency.

Greater Manchester Police today confirmed it is investigating the claims following "the information provided to us by Mr Daly."

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