MANCHESTER Mayor Andy Burnham stoked speculation of a challenge to Sir Keir Starmer by refusing to rule out one against the beleaguered Prime Minister today.

“I am not going to sit here this morning and rule out what might or might not happen because I don’t know what the future will hold,” he told the BBC.

In fact, Mr Burnham cannot run for the leadership until he is an MP once more and, while his hat is in the ring, he himself is not in the arena.

Nevertheless, he set out his own agenda for governance, saying “The country is crying out for a plan for growth that benefits people, reduces the cost of living.”

He also said he appreciated Norwich South MP Clive Lewis’s gesture in offering to give up his Commons seat in his favour.

That, however, is unlikely to come to anything. While Mr Lewis can certainly resign his seat, Labour’s executive and not the outgoing MP would choose the candidate for the subsequent by-election.

Mr Burnham is widely thought to have overplayed his hand at Labour conference by openly trailing his ambitions to succeed Sir Keir.

Undaunted, he said today: “I’m providing leadership on growth, which is what I think the country needs.

“I think part of the country’s problem is, the political culture of Westminster, which is playing out in front of us right now.

“In Greater Manchester, we’ve built a new economy and a new way of doing politics and more of that is what the country needs.”

His manoeuvres come as it is reported that the Tribune group of MPs, broadly the “soft left” of the Parliamentary Labour Party, have secured the support of the 80 MPs required to nominate a challenger to the Prime Minister.

This follows last week’s astonishing briefing wars launched by Downing Street against possible rivals to Sir Keir, most prominently Health Secretary Wes Streeting.

MPs the group might back, in the absence of Mr Burnham, include newly elected deputy leader Lucy Powell, former transport secretary Louise Haigh and Culture Secretary Lisa Nandy.

Ex-leader Ed Miliband has ruled himself out, while former deputy premier Angela Rayner, probably the most popular choice in the country, may feel an early contest is too soon for her after she quit government over a row about stamp duty.

What is beyond doubt is that support for Sir Keir has collapsed among Labour MPs. Few believe that he has the capacity to turn around Labour’s desperate position in the opinion polls, nor supply the government’s missing sense of purpose and direction.