The prospect of widespread strikes by public sector workers over planned cuts to their pensions is set to come closer when union activists discuss the Government's "attack" on them.
The GMB annual conference in Brighton will discuss the changes to their pensions, with delegates expected to claim that the Government's proposals were based on "inaccuracies and lies".
Average annual pensions from public sector schemes were only £7,000 a year, the union will point out in a bid to counter claims of "gold plated" payouts.
A motion to be debated reads: "We call for a joint trade union national campaign to highlight the attacks planned by this vicious government and the effects these will have on the future provisions of local government workers."
Delegates will also discuss the prospect of campaigning with other public sector unions to defend pensions "including industrial action if necessary."
The GMB is not involved in plans for co-ordinated action on June 30, so the debate could herald warnings of action later in the year.
Union leaders have warned that crucial talks aimed at heading off strikes over pensions could be hit after Business Secretary Vince Cable said that widespread industrial action could ratchet up pressure on the Government to strengthen strike laws.
The minister was heckled when he addressed the GMB conference on Monday despite going out of his way to stress that the right to strike was a "fundamental principle". Several parts of his speech were interrupted by shouts, boos and catcalls from delegates, while some held up a banner which read: "Vince Cable not welcome - Stop Attacking Workers' Rights."
One of the final round of talks aimed at resolving a simmering row over cuts to public sector pensions is due to be held on Thursday between the Government and leaders of several unions. Some union officials warned that Mr Cable's warning had soured the atmosphere and made it less likely that a deal can be reached this week.
Andy Clarke, chief executive of supermarket giant Asda, will address the GMB conference, the most senior business leader ever to talk at the annual event.