As dozens of MPs sign a letter criticising Burnham’s decision, Starmer is facing an increasing Labour uprising.

Sir Keir Starmer, the leader of the Labour Party, is facing a growing rebellion from Manchester Mayor Andy Burnham regarding the decision to bar Burnham from standing in a by-election in the city, with almost 50 Labour MPs reportedly signing a letter objecting to this decision.

He is said to have written to the Prime Minister, warning that the decision was “a real gift.” Polling suggests that Mr. Burnham may be Labour’s “best chance of winning” the vacant Gorton and Denton seat.

A 10-strong group of Labour’s ruling National Executive Committee (NEC), including Sir Keir, voted to refuse Mr Burnham permission to contest the election. The decision was made during a meeting on Sunday regarding the Greater Manchester by-election.

Mr Burnham’s candidacy for factional reasons,

Critics have accused Sir Keir and his allies of blocking Mr Burnham’s candidacy for factional reasons, fearing a leadership challenge from the mayor as both Labour’s poll ratings and his personal approval ratings have declined.

But the Prime Minister has insisted that an additional election for the mayor of Manchester would “divert our resources away from local elections,” which are already expected to be extremely painful for the Labour Party.

However, the letter’s signatories argued that there was “no legitimate reason” to exclude Mr Burnham, urging Labour’s NEC to reconsider the decision.

It came as Reform leader Nigel Farage said he felt his party’s chances of winning the seat would have been improved by not standing in the Manchester mayoral by-election, admitting that “it would have been very difficult for us to beat him.”

We expect the Gorton and Denton by-election to take place on 26 February, following the resignation of former MP Andrew Gwynne for health reasons.

Reform UK will announce its candidate for the contest at a press conference in the constituency on Tuesday, a day after Mr Farage claimed his party’s prospects are “much better” than before as a result of Labour’s decision.

Labour’s left-wing political rival, the Green Party, is also considering its chances in the race.

The stir over the Gorton and Denton by-election comes as Sir Keir Starmer is set to embark on a trip to China that will take him out of the domestic political arena for several days.

On Monday, the prime minister was among senior Labour figures trying to focus his MPs’ minds on the by-election after facing criticism for blocking Mr. Burnham’s application to stand in the race.

Sir Keir was one of a 10-strong group of Labour’s ruling National Executive Committee (NEC) that voted to refuse to allow the Greater Manchester mayor to run at a meeting on Sunday.

The Prime Minister faced criticism from the left of the party and trade unions for the move but defended the decision and insisted that “the battle of our time” was between Labour and Reform UK.

At a gathering of Labour’s backbench MPs on Monday night, Attorney General Lord Harmer – who is a close ally of the PM – also urged MPs not to focus on internal party politics, while Labour chair Anna Turley spoke about the need to go to the election with a “positive message.”.

Left-leaning Labour MPs are understood to have asked questions about the impact of not allowing Mr Burnham to stand during a parliamentary Labour Party meeting.

But senior party leaders have reportedly admitted privately that they now expect Mr Burnham to lose the by-election after he was barred from standing.

The Times also reported that some feared Labour could be pushed to third place behind Reform and the Greens, as Sir Keir decided that losing the seat was a price worth paying to retain the Greater Manchester mayoralty.

Mr Burnham, who said in a statement on Sunday he was disappointed by the move, has meanwhile not completely ruled out a return to Westminster in the future, according to the Guardian.

The newspaper also said Sir Keir has offered his support to Mr Burnham to contest another northwest seat in 2027, near the end of his mayoral term when Labour can field a strong replacement figure.