In an interview with the New Statesman, Burnham said: “I’m going to put the question back to people at Labour conference. Are we up for that wholesale change? Because I think that’s what the country needs.
“If you’re asking me, am I attracted to going back into my old world and the old way of doing things in Westminster with minimal change, well no, I wouldn’t find that attractive.
“[But] am I ready to work with anybody who wants to sort of put in place a plan to turn the country around? I’m happy to play any role.
“I am ready to play any role in that, yes. Because the threat we’re facing is increasingly an existential one.”
Burnham did not refer to Reform directly but his remarks will be seen as a nod to the party’s rise amid Labour’s collapse in popularity. Farage is on course to win a Commons majority if current polling continues.
Starmer’s first 15 months in Downing Street have been overshadowed by a number of scandals, including the resignation of Angela Rayner as deputy leader and the sacking of Lord Peter Mandelson as United States ambassador.
The Prime Minister was also forced into climbdowns on winter fuel payments, welfare cuts, and a national grooming gangs inquiry.
Burnham had openly challenged the Government on all three policies, saying he would not “parrot” its line on winter fuel cuts, branding benefit cuts “the wrong choice” and calling for an inquiry months before Starmer’s about-turn.
In the clearest sign yet that he is preparing to challenge Starmer, the mayor declined to commit to seeing out his full term in Manchester, which ends in 2028.
He is also among the supporters of Mainstream, a new soft-left pressure group, which has already accused Starmer of putting party factionalism before national interest.
Burnham echoed these criticisms in his interview with the New Statesman.
“The political system doesn’t feel like it works for people, does it? To me, the issue of the conference is not who is the deputy leader of the party, who is the leader of the Labour Party.
“The issue for the conference is: where is our plan to turn the country around?” he told the left-wing magazine.
“This kind of challenge we’ve got in front of us cannot be met by a very factional and quite divisive running of the Labour Party.”
Seeking to downplay his immediate leadership ambitions, Burnham insisted he did not spend “every waking moment” thinking about the idea of challenging Starmer.
But he added: “Politics BAU – business as usual – Westminster politics, ain’t gonna do it. The plan has to change quite radically.”
As well as breaking with the party line to demand proportional representation, he went further than any Cabinet minister by calling the asylum hotel system “atrocious” and “dangerous”.
Burnham, who staunchly campaigned for Britain to remain in the European Union, also called on Starmer to argue in stronger terms that Brexit had “been a mistake”.
The Labour conference begins on Sunday, when Burnham will address a rally calling for electoral reform in order to “renew Britain’s democracy”.
The 55-year-old made two previous attempts at the Labour leadership, coming fourth in 2010 and a distant second to Jeremy Corbyn in 2015, although he is not eligible currently to stand because he is not an MP.
Burnham admitted it would be a “wrench” to abandon his current position and life in Greater Manchester but once again declined to rule out a tilt at the leadership.
Asked directly about his ambitions, he said: “Well … I love this job here, I love what I’ve been able to be part of here.
“I think people don’t realise what a wrench it would be for me to leave here. I mean it when I say that the life I have here matters greatly to me.”
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