LABOUR should be wary of fair-weather friends motivated by “personal vanity,” general union Unite has said after a businessman offered a cash donation if the union disaffiliated.

Hull City FC owner Assem Allam was linked to a deal allegedly brokered by former PM Tony Blair in which the businessman would donate an additional £500,000 if Unite ended its support for the opposition party.

“I hope I can inspire other like-minded business people to do the same so that the Labour Party can stand on its own without having to satisfy one paymaster,” Mr Allam told the Sunday Times.

But Unite general secretary Len McCluskey said: “A Labour Party victory will not be won on the back of one-off donations from fair-weather supporters.

“The labour movement is built on its values, not money.

“If Allam truly wishes to support Labour, he should lead by example and adopt our values by paying his staff at Hull City a living wage.”

The war of words erupted as Unite-backed Karie Murphy was controversially excluded from the longlist of potential candidates for Labour’s late selection in the Halifax constituency

A panel from Labour’s national executive was responsible for the decision and included Labour deputy leader Harriet Harman, youth representative Bex Bailey and union representative Jim Kennedy.

Party sources have suggested that Ms Harman and Ms Bailey were chosen from the wider special selections panel with the specific intention of excluding Ms Murphy.

The Unite candidate’s previous attempt to win selection in Falkirk, Scotland, was torpedoed when top Blairites accused Unite of impropriety.