Andy Burnham will not take a job in Sir Keir Starmer's Government if he wins the Makerfield by-election, sources close to the potential Labour leadership challenger have said.
Allies of the Mayor of Greater Manchester ruled out Mr Burnham accepting a role in a government led by Sir Keir, as first reported by the Manchester Evening News (MEN).
Sir Keir had earlier offered an olive branch to Mr Burnham, and said he wants him to play a big part in the Labour Government, an apparent signal he could invite him to join the Cabinet.
Mr Burnham hopes to win in the Makerfield by-election on Thursday and secure a return to Westminster as an MP, and has made no secret of his Labour leadership ambitions.
A source close to him also suggested to the MEN he was not interested in the offer from Sir Keir, telling the paper the benefit Andy has is the wind of change for not having been associated with the Government's failings.
Discussion of Greater Manchester mayoral elections to replace Mr Burnham by those at the centre of Labour were an attempt to put further challenges up, the source added, claiming that if Sir Keir remains as Prime Minister it will give people an excuse to vote against Labour in the mayoral poll.
Sir Keir repeated on Wednesday that he would not walk away from his post and intended to fight any challenge.
The Prime Minister is also facing a looming threat from his former health secretary Wes Streeting, who has indicated he is prepared to trigger a Labour leadership contest as early as next week.
Sir Keir appeared to suggest he could bring Mr Burnham into his Government in comments to Sky News. Andy is a great asset. And, yes, I want him to have a big role in government.
Asked if he would call Mr Burnham at the weekend and invite him to join the Cabinet if he wins in Makerfield, the Prime Minister said: Well, I'm sure I'll talk to Andy after the weekend, of course I will. I've spoken to him many times in recent weeks.
The Prime Minister insisted the focus would fall immediately to a contest to replace Mr Burnham in his mayoral seat if he became an MP.
Asked what preparations he was making for a potential Labour leadership contest, he told reporters: First and foremost, I want Andy Burnham to win, and that's why I've encouraged activists and members to go up there during the course of the campaign, and they'll be up there tomorrow helping to get the vote out.
Then what happens is we're immediately tipped into a Manchester mayoral contest by-election, one of the biggest by-elections that we've ever fought, because of the scale of it.
And it's really important to my mind that the whole of the Labour Party and Labour movement focuses on that, which is the next most immediate task.
I don't think there should be a challenge. I think history, particularly the last government, shows that that isn't a successful way for a government to behave.
But if there is a challenge, then I intend to fight. I'm not going to walk away from that, and I've been clear and consistent about that.
Mr Streeting meanwhile said he has the backing of the 80 MPs required to stand in a contest and accused Sir Keir of not listening to the party or his Cabinet, in a series of public appearances on Tuesday.
