It appeared she believed she needed to remain impartial given her role overseeing the committee.
Yesterday, Burnham declared his intention to stand in the byelection. Winning the seat and returning to Westminster would potentially have allowed him to launch a leadership challenge against Starmer.
However, he needed the backing of Labour’s NEC, which is controlled by allies of the Prime Minister.
In a statement Burnham said: “I am disappointed by today’s NEC decision and concerned about its potential impact on the important elections ahead of us. To whoever is Labour’s candidate and to our members in Manchester and Tameside: you will have my full support and I will be there whenever you need me.”
Starmer’s supporters argued that allowing Burnham to seek a House of Commons seat would have risked Reform UK winning control of Manchester in a subsequent mayoral byelection.
Sources accused Burnham of putting his personal ambition before the party, given that if he stood, then a new vote for the Greater Manchester mayoralty would be triggered.
But the blocking of Burnham, which will be seen by critics as a naked attempt to thwart a potential Starmer leadership rival, set off a backlash.
Mainstream, the soft-left group closely aligned with Burnham, said in a statement: “Labour must reverse this decision if it is serious about putting country before party. We urge the party to reconsider in the interests of taking on Reform and building the strongest possible team in Westminster.”
The Prime Minister is facing anger from backbenchers on the left of Labour who had backed Burnham’s candidacy. The decision could tip the party into civil war at a time when it is lagging behind in the polls.
Labour MPs are circulating a letter seeking to overturn the decision.
The letter to Starmer, which is being circulated by the left-wing MP Clive Lewis, urges the full NEC to “re-evaluate” its decision and let the local party in Gorton and Denton decide whether Burnham should be the candidate.
The letter warned that losing the byelection would be “unimaginable ... blocking him from even making his case to local members risks sending a message that the party does not respect devolution”.
It added: “It risks telling our own local members that we do not trust them to make the important decision on who is best placed to fight this election for them and serve as the next MP. Fundamentally it risks playing into the kind of division and disunity that Nigel Farage and Reform thrive on.”
John McDonnell, the former shadow chancellor under Jeremy Corbyn, said the NEC – as the governing body of the party – had the authority to overrule the panel that blocked Burnham.
Earlier, he had posted on X: “Message to Keir: Do not underestimate the depth of anger people will feel about this disgusting decision. If you think it strengthens you I tell you it will simply hasten your demise. You could have shown magnanimous leadership but instead it’s cowardice.”
Louise Haigh, the Labour MP and Starmer’s former transport secretary, said it was “disappointing” and suggested it should be reversed.
She told the Telegraph: “This is an incredibly disappointing decision. There’s no point pretending we don’t have a problem connecting with the public at the minute.
“The leadership should not feel threatened by having one of the most popular politicians in the country as part of the national team.
“It’s not too late to change course and make the right decision. Otherwise I think we’ll all come to regret this.”
Jon Trickett, the Labour MP for Normanton and Hemsworth, told the Telegraph: “The decision to prevent members having a full choice of available candidates reveals weakness and lack of confidence in Downing Street”.
One Labour MP on the left of the party said the decision made the Labour leadership look “absolutely p*** weak” and would embolden those seeking to install Wes Streeting, the Health Secretary as leader.
Starmer’s allies claimed that permitting Burnham’s candidacy would have cost Labour hundreds of thousands of pounds to fight a mayoral election. It would have risked Manchester falling into the hands of Nigel Farage’s party, they said.
An ally of Starmer warned before the NEC decision that triggering a new election for the Greater Manchester mayoralty would have led to a “nasty and divided” campaign that could have seen Reform win control of the city.
The source said: “We would never forgive ourselves. It would be political madness to give up one of the biggest cities to Reform. We should not gamble with people’s lives and communities like that.”
The ally warned against “turning inwards and doing a bad version of Tory psychodrama” and questioned whether the “ambition of one man” was worth it for the party.
Steve Reed, the Communities Secretary, suggested the reason to block Burnham was to spare the voters of Greater Manchester an election.
He told the BBC: “Voters don’t like elections that come mid-term. People voted in Greater Manchester overwhelmingly for Andy Burnham to be their mayor two years ago, for a four-year term.
“So we’re not going to go back and ask the people of Greater Manchester, over two million of them who are entitled to vote, to elect somebody else to complete the next two [years], because we can select a different candidate for the Gorton and Denton byelection, and we will make the case for the Labour Government.”
Supporters of Starmer had claimed that Burnham’s comment last autumn that Labour was “in hock to the bond markets” had added £1 billion in higher interest payments as markets were spooked by the prospect of him becoming leader.
Burnham, who is known as the “King of the North”, had secured the backing of several senior figures on the left of the party before his attempt to stand was blocked, including Ed Miliband, the Energy Secretary and former Labour leader, Sadiq Khan, the Mayor of London, and Powell.
Streeting, who is considered a future leadership candidate from Labour’s right, previously criticised “disgraceful” briefings against Burnham but stopped short of backing his candidacy.
Blocking Burnham could embolden other potential leadership contenders such as Angela Rayner and Streeting, both by creating a new grievance for many backbenchers and removing a powerful rival.
The party’s chosen candidate in Gorton will face a major challenge from the ascendant Reform UK, which came second in the seat in 2024.
Andrew Gwynne, the Labour MP who represents the seat, said last week that he would stand down.
Many in the party fear that if Labour loses to Farage’s party now that Burnham has been blocked, it will be a fatal blow for the Prime Minister.
Burnham is also likely to feel free to step up his criticism of No 10.
The mayor, who has twice run to become Labour leader and held Cabinet positions under former leader Gordon Brown, has made no secret of his desire to become Prime Minister.
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