Speculation has spread over whether Burnham will attempt to return to pursue a Labour leadership bid

Keir Starmer’s allies have launched a “Stop Andy Burnham” campaign to prevent the Labour mayor from returning to parliament after the resignation of a Manchester MP triggered a byelection.

Multiple members of the party’s ruling national executive committee (NEC) predicted it would be impossible for Burnham to make it through the selection process given the number of Starmer loyalists on the body desperate to avoid a leadership challenge.

The Labour party machine sprang into action after the Guardian revealed on Thursday that Andrew Gwynne was planning to quit due to ill health, with officials and MPs warning about the financial cost and political risk of a subsequent mayoral race.

However, allies of the Greater Manchester mayor suggested there would be significant disquiet among MPs, the unions and party members should the leadership try to block him from returning to parliament, where he served as the MP for Leigh from 2001 to 2017.