Andy Burnham has secured his return to the House of Commons as his allies called on Sir Keir Starmer to hand over power.
The Greater Manchester mayor won the Makerfield by-election by 9,231 votes, seeing off the challenge from Nigel Farage’s Reform UK.
Mr Burnham’s victory sets up a potential leadership contest unless the Prime Minister agrees to step down.
Sir Keir has insisted he will fight any attempt to challenge him and has been building up a war chest for a leadership campaign.
But Mr Burnham’s supporters urged the Prime Minister to set out an “orderly and managed transition” of power.
Former cabinet minister Louise Haigh said she hoped Sir Keir will “do what’s best for both the country and the Labour Party”.
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