In defiance of the Prime Minister and many other senior figures in the party, Labour's big union battalions have decided to back Ken Livingstone's application to rejoin the party.
Most of the unions have decided to vote in favour of the maverick Mayor of London's readmission when the national party decides the issue on 23 July. Unions hold 12 out of 32 votes on the party's national executive, but command influence among representatives from constituencies.
The public service union, Unison, the Transport and General Workers' Union, the GMB general union and the Communication Workers Union are understood to be among those which will vote for reinstatement.
A document from Unison's Labour Party committee states that the party needs to "achieve maximum unity" going into the next mayoral election in 2004 and declares that it will urge the union's representatives on Labour's national executive committee to vote for readmission.
The growing support for Mr Livingstone's reinstatement among unions follows a nine-to-three vote to readmit him by the party's ruling body in London. A recent meeting of London Labour MPs backed the Mayor and so did a majority of Labour members of the London Assembly.
Tony Blair, John Prescott, the Deputy Prime Minister, and Gordon Brown, the Chancellor, are all opposed to Mr Livingstone being allowed an early return from his five-year exile for standing against Frank Dobson, the official Labour candidate for Mayor, two years ago. The party will have to finalise the process for selecting its candidate in the next mayoral elections by the end of the year.
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies