Unions have made clear to Labour they will not give up their collective voice despite moves to reform the link between the party and union members.
In a short debate on the opening day of the party's annual conference in Brighton, leader Ed Miliband was told that unions were capable of recruiting members, but their collective voices will not be "washed away for an electoral gimmick".
Mr Miliband wants union members to opt into party membership rather than be automatically affiliated, a controversial move which led the GMB to decide to cut its affiliation funds to Labour by over £1 million from next year.
GMB general secretary Paul Kenny told the conference that debates during the coming days should be about jobs, homes, living standards and employment rights, not "navel gazing" about internal party structures.
Speaking on behalf of the 14 unions affiliated to Labour, Mr Kenny said an interim document by Lord Collins on the planned reforms, started, not ended the process.
"The desire to expand party membership is a shared one, but let nobody be under any illusion that as collective organisations, the removal or sale of our collective voice is not on the agenda.
"We are certainly not going to accept any advice on democracy and transparency from the people who brought us the cash for honours scandals, or whose activities are funded by cash from wealthy outsiders who refuse to give to the party but prefer to lay cuckoos in CLP nests.
"We can expand ad infinitum the number of people we bring into then tent, but if what they say is ignored, as has been the case in the past, in favour of dinner party babble, then why bother?
"Be assured, the collective voices of millions of working people and their families, and 100 years of shared history, will not be washed away or sold for an election gimmick."
Mr Kenny received a standing ovation from union leaders inside the hall.