Sir Keir Starmer said Andy Burnham is doing a “great job” as Greater Manchester mayor but allowing him to run for a Westminster seat would “divert our resources” from Labour’s campaigns in May elections.
The Prime Minister insisted the “battle of our times” was between Labour and Reform rather than within his own party despite internal anger over the move to block Mr Burnham from standing in Gorton and Denton.
He appealed for unity within the party as it braces for local elections in spring, urging members and MPs to “line up together” to play a part in “a fight that matters hugely to the future of our country”.
A 10-strong group from Labour’s ruling National Executive Committee (NEC), including the Prime Minister, voted to deny Mr Burnham permission to run in the Greater Manchester by-election at a meeting on Sunday.
Critics have accused Sir Keir and his allies of preventing Mr Burnham’s candidacy for factional reasons, fearing a leadership challenge from the mayor as both Labour’s poll ratings and his personal approval flounder.
The Prime Minister faced questions about the move on Monday as he visited a health centre in Wimbledon, southwest London, with Health Secretary Wes Streeting – another potential leadership rival who would benefit from the absence of Mr Burnham if he chose to stand in any contest.
Speaking to broadcasters, he said: “We have really important elections already across England for local councils, very important elections in Wales for the government there, and very important elections in Scotland for the Scottish government that will affect millions of people.
“And we’re out campaigning on the cost of living, and they’re very important elections.
“We need all of our focus on those elections.
“Andy Burnham’s doing a great job as the Mayor of Manchester, but having an election for the Mayor of Manchester when it’s not necessary would divert our resources away from the elections that we must have, that we must fight and win, and resources, whether that’s money or people, need to be focused on the elections that we must have, not elections that we don’t have to have.
“And that was the basis of the NEC decision.”
Former cabinet minister and backbencher Louise Haigh said on Sunday Labour’s ruling body should reverse its decision “otherwise I think we’ll all come to regret this”, while Simon Opher MP called the decision an “own goal” for Sir Keir’s advisers.
Another backbencher told the Press Association they expected Labour would now lose the Gorton and Denton by-election.
Trade unions also criticised the decision, with the TSSA saying the party had “lost its way” and the general secretary of Unison, Britain’s largest trade union, saying it was not the way “any democratic organisation should be run”.
Asked for his response to accusations of cowardice from within his own party, Sir Keir suggested that Labour rules hold that the “presumption” is against “introducing an election which we don’t have to have.”
“The question the NEC had to address was whether we should take the focus away, which it would have done, from the elections in Wales, in Scotland, and the elections we must have by introducing an election which we don’t have to have,” he said.
“And two years ago, the Labour Party changed the rules to say the presumption is really against doing that, because we need to fight where we must fight.”
Pressed on what his message would be to a divided and unsettled party, the Prime Minister said the party “must never lose sight” of what matters most to the public, namely the cost of living.
He added: “The second thing I’d say is there is a fight, yes, there is a fight, but that fight is with Reform, and we all need to line up together to be in that fight, all playing our part.
“I think that everybody in the Labour Party, everybody who’s a Labour MP, wants to be in that fight, wants to fight alongside all their colleagues in a fight that matters hugely to the future of our country.”
He said he had a good working relationship with Mr Burnham, citing how they responded together to the synagogue attack in Manchester last year.
The Greater Manchester Mayor has said he was “disappointed” by the decision and “concerned about its potential impact on the important elections ahead of us”.
In a statement on social media, he insisted he would “return with full focus” to his mayoral job on Monday and urged unity in the face of “the divisive politics of Reform”.
But he said the fact the NEC’s decision had been leaked to the press before he had been informed “tells you everything you need to know about the way the Labour Party is being run these days”.
Labour sources have strenuously denied that the party leaked the decision before informing Mr Burnham, and said they attempted to contact him shortly after the meeting by phone and email.
Other backbenchers supported the NEC’s decision, urging the party to avoid infighting and move on to winning the by-election.
Phil Brickell, who represents the Greater Manchester constituency of Bolton West, said speculation about Mr Burnham’s candidacy in recent days had “seen the Labour Party quickly turn inward… undermining the PM’s efforts at home and abroad”.
Rugby MP John Slinger said the “quick and clear decision” meant the party could “move on from the damaging, introspection and psychodrama of the last week” and “pull together” behind the eventual candidate.
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