Keir Starmer has watered down his previous pledge to end arms sales to Saudi Arabia if he becomes prime minister.
The Labour leader would only commit to a “review” of the policy if he becomes prime minister.
Starmer also appeared to row back on his previous commitment to bring in a new law forcing the government to seek parliamentary approval for any military action.
When he was running to succeed Jeremy Corbyn in 2020, Starmer said the UK “should stop the sales of arms to Saudi Arabia”.
But on Sunday with Laura Kuenssberg this morning, he said: “We will do a review to look at the sales, look at the countries and the relationships that we have. Obviously, that follows a review.”
Kuenssberg told him: “But you said in February 2020 ‘we should stop the sale of arms to Saudi Arabia’. Is that still your position?”
Starmer replied: “We will review the situation and the review will give us the answer to those questions.”
Kuenssberg said: “So you may not any more promise to stop the sale of arms to Saudi Arabia, which is what you used to say in 2020.”
Starmer said: “We will review the situation and the review will make clear what the position is.”
During his leadership campaign, Starmer pledged to “end illegal wars” by introducing a Prevention of Military Intervention Act.
That would ensure that any military action had to be legal and backed by a Commons vote.
However, Starmer backed last week’s air strikes on Houthi rebels in Yemen despite there being no vote in parliament beforehand.
Asked about the apparent change of heart, the Labour leader insisted there was “no inconsistency” in his position.
He said: “There is a huge distinction between an operation the like of which we’ve seen in the last few days and a sustained campaign - military action usually involving troops on the ground.
“National security must come first. There will always be urgent situations where parliament can’t be consulted beforehand. But the principle that if there’s to be a sustained campaign, if we’re going to deploy our troops on the ground, that parliament should be informed, there should be a debate, the case should be made and there should be a vote, I do stand by that in principle, absolutely.”
However, Starmer refused to commit to introducing a new law, saying it could be “done by some other means”.