Labour is to face challenges over its links with one of its biggest union affiliates after union member expressed widespread anger and "disgust" at the party's policies towards workers.
The union has already cut back the amount it gives Labour following outrage at a speech by Shadow Chancellor Ed Balls on support for the government's freeze on the pay of millions of public sector workers.
A series of motions will be debated at the GMB's annual conference in Brighton tomorrow, including calls to disaffiliate from Labour and withhold funds from MPs, and support for any "left alternative" to the party.
The GMB gives Labour around £1.4 million a year in affiliation fees, but since Mr Balls made his comments last year, the union has cut back on more than £500,000 in other money it gives the party, it can be revealed.
The 500 delegates will tomorrow be asked to approve a special report by the GMB executive which details a new political campaign, including the reinstatement of political education courses and re-establishment of regional political officers.
GMB are to challenge Ed Balls on his support of pay cuts for public sector workers, amid anger over the lack of support the party has offered workers
The executive wants to be addressed by Labour's leader and deputy leader at least once a year, as part of a "new direction", which includes reorganising its political structures.
"It is time to make ourselves heard above the chatter of the dinner party brigade," said the statement.
GMB general secretary Paul Kenny said there were enough lawyers in Parliament, so it was time to encourage "ordinary members of the public" to stand as candidates to become councillors or MPs.
It is set to launch a campaign to encourage more working class people into politics, spending more money on political campaigning at the expense of Labour party funding.
"We have care workers who cannot get time off, or afford to travel, up against lawyers from London in selection campaigns, so we should be offering people like that financial support.
"We have to get people interested in politics so that our voice can be heard on issues like employment law and trade union rights. I don't think we should pull out of the Labour Party at this stage, but what we are not going to do is compromise our core position on issues which affect us."
Mr Kenny said many union members were "bemused" at comments from Labour figures such as Mr Balls on public sector pay, and wanted the party to make it clear they will reverse the coalition's policies in areas such as the NHS.
"The party has to move on from the rhetoric of attacking the coalition for cutting too fast and too deep, and set out what a post-Tory government will look like.
"Will they reverse privatisation in the NHS, because if they don't, they will lose support from working class people."
Mr Kenny said the policies pursued by New Labour had completely failed, but some groups were trying to "carry the flame" of support for privatisation of public services and opposed improvements to trade union and employment rights.
Mr Balls will address the GMB conference tomorrow and take questions from delegates.