SIR KEIR STARMER was accused of “serial duplicity” today after he backtracked on pledges to prevent illegal wars.

When running to succeed Jeremy Corbyn in 2020, he vowed to introduce a law allowing MPs to vote on military intervention and said Britain “should stop the sale of arms to Saudi Arabia” amid concerns about their use in the Yemeni civil war.

He promised a “prevention of military intervention act” under commitments to stop “more illegal wars,” saying that he would pass legislation ensuring military action could only be taken if a lawful case was made, there was a viable objective, and consent from Commons had been given.

But today — following his swift support for Prime Minister Rishi Sunak’s authorising RAF strikes against the Houthis in Yemen, in partnership with the US, without consulting Parliament — the Labour leader said giving the Commons a say may no longer be introduced as a law and was not definitive about the review when it came to the Saudis.

Sir Keir insisted that he still wants to bring in the change, but argued that it would only relate to sending in ground forces and that he stands by his pledge “in principle, absolutely.”

He also told the BBC that the alteration may not need to be in law: “I want to codify that — it could be by a law, it could be by some other means. I’m not ruling out law.”

He also claimed that there was “no inconsistency” between his previous promise and his support for strikes against the Houthis.

“There is obviously a huge distinction between an operation, the like of which we have seen in the last few days, and military action, a sustained campaign, military action usually involving troops on the ground,” he said.

Today, a spokesman for Momentum said: “Labour members and the British public deserve better than serial duplicity.

“By unconditionally backing the US-led bombing of Yemen, Starmer is repeating New Labour’s mistakes.

“This is not the policy of peace and human rights we were promised.”

Diane Abbott MP, shadow home secretary under Jeremy Corbyn, quoted Sir Keir’s 2020 pledges, saying the current military action on Yemen has not been shown to be legal, nor to have a “viable objective.”