JEREMY Corbyn will stand down as UK Labour leader if he loses the impending general election, his closest ally has said.

Shadow Chancellor John McDonnell told GQ magazine he “can’t see” how Mr Corbyn could stay on if he lost a second time, and said the next leader must be a woman.

He thereby ruled himself out, but it was also an implicit snub to deputy leader Tom Watson and Shadow Brexit Secretary Sir Keir Starmer.

The comments risk a rift at the top of the Labour party as it prepares for an election Mr Corbyn says he is “champing at the bit” to fight.

Many of his MPs fear it will see the party being crushed between a Tory revival under Boris Johnson and Labour Remain voters defecting to the LibDems over Brexit.

Mr McDonnell was interviewed by Tony Blair’s former spindoctor Alastair Campbell.

The Shadow Chancellor said he thought Labour could win a majority at the election, but if it was a minority government there would be “no deals” with the LibDems or SNP.

He said: “We’ll just lay out our programme and they either support it or they don’t. If they don’t support it we’ll go back to the country.

“No backroom deals whatsoever and we’re not going to be held back by any other political parties.”

Asked if Mr Corbyn could stay on if he lost the next election to the Tories, Mr McDonnell replied: “ I can’t see... I think it is the same for my own personal position, I can’t see so.

“What we’d do is as the tradition, which is have an election for a new leader. I’m still of the view now that whoever comes after Jeremy has got to be a woman. We’ve got to have a woman leader. If you look at the new youngsters that have come through, they are fantastic.”

He added: “We’ve got such a range of talented women in the shadow cabinet that it’s obvious it’s going to be a woman next time.”

After Mr Campbell suggested Shadow Foreign Secretary Emily Thornberry and Shadow Business Secretary Rebecca Long-Bailey, Mr McDonnell added Shadow Education Secretary Angela Rayner to the list.

Although Labour did better than expected in the snap 2017 election, it got 56 fewer seats than the Tories.

Mr Corbyn has declined to say what he would do if he lost again.

Asked by a reporter on Thursday if would stay on, he did not respond to the question, while some of his supporters said he didn’t need to go.

When asked about the next election, a source close to Mr Corbyn said: “We’re in it to win it.”

Elsewhere in his interview, Mr McDonnell said the Prime Minister was dangerous because he was not guided by principles or beliefs.

He said: “I think this is the ruthless pursuit of power for power’s sake. That is why I caution him to be careful with what he’s unleashing.

“You’ve got a politician who, literally, truth doesn’t matter to... attacking the institutions that protect our democracy – parliament, judges, the rule of law.

“Once you get into that territory you’re into danger territory, and you don’t know again how that will wind up. I think there are real issues there and lessons we’ve got to learn.”