Andy Burnham has announced that he is seeking permission to stand in the upcoming Gorton and Denton parliamentary by-election.
If he won and became an MP, Burnham could mount a leadership challenge against Sir Keir Starmer but the BBC has been told that allies of the prime minister may try and block him from standing in the constituency.
Burnham is currently mayor of Greater Manchester and in a statement insisted that he wants to back the Labour government “not undermine it”, adding that the decision to announce his intentions had been “difficult”.
The seat in Greater Manchester is vacant after Andrew Gwynne stood down on Friday as an MP on health grounds.
As a directly-elected mayor, Burnham has to get approval from Labour’s ruling national executive committee before he can enter the race to be the party’s candidate.
Several Labour MPs have reacted angrily to the suggestion that he could be blocked from standing.
Some senior figures in the party have also said they believe Burnham should be allowed to stand.
London Mayor Sir Sadiq Khan said: “If Andy Burnham wants to be a member of Parliament, Andy Burnham should be allowed to be a member of Parliament”.
Energy Secretary Ed Miliband said Burnham would be a massive asset” in Parliament and that he hoped Gorton and Denton party members would have “the option” of selecting him as a candidate.
In his letter to the NEC, which he shared on social media, Burnham said there was a “direct threat to everything Greater Manchester has always been about from a brand of politics which seeks to pit people against each other”.
“I see this by-election as the frontline of that fight for the Manchester Way and I feel I owe it to a city which has given me so much to lead it from the front, despite the risks involved.”
He said he had left Westminster nearly a decade ago because he believed “it wasn’t working for people in our part of the world” and that as mayor he had “tried to pioneer a different way of doing things”.
However, he added that he believed Manchester “won’t be able to be everything it should be without similar changes at a national level.
“This is why I feel the need to go back.”
There has been speculation that the prime minister could face a leadership challenge, after the May elections, which will see votes take place in the Welsh Parliament, the Scottish Parliament and in some local councils in England.
Burnham has been touted as a possible leadership contender but can only mount a bid if he is an MP in the Commons.
In his letter to the NEC, Burnham insisted he would be in Parliament “to support the work of the government, not undermine it”.
“I have passed this assurance on to the prime minister.”
If he were to be selected and won the Gorton and Denton seat, Burnham would have to resign as Greater Manchester mayor, triggering a new election for that role.
Several Labour sources have said the NEC could block Burnham’s application on the grounds that a mayoral election would be expensive for the party.
It would also be costly for the taxpayer with the last mayoral election costing around £4.7m.
The NEC is expected to inform Burnham of their decision on Sunday.
