Labour leader Ed Miliband has told union leaders that their members and the public did not want strikes, amid the growing prospect of industrial action against the Government's austerity measures.
Mr Miliband risked sparking an angry reaction from unions by speaking out against strikes just hours after teachers' leaders announced a campaign of industrial action.
The Labour leader attended a dinner with the TUC general Council in Brighton, where the annual TUC Congress is being held, and was expected to say: "It's what's happening in our economy that makes so many people angry with the Government. The question is how best to get them to change course? The public doesn't want to see strikes. Nor do your members. Nor do you."
He continued: "The way to sort out the problems the country faces is for the government to understand why working people are so unhappy. It's because the economic plan is failing, it's unfair. They need to change before greater long-term damage is done."
Shadow chancellor Ed Balls, who is to address the conference, was attacked by union leaders for supporting pay restraint in the public sector, and Mr Miliband's comments will not go down well with some activists.
Members of the two biggest teaching unions will launch a campaign of industrial action short of a strike from September 26, with the threat of walkouts later this year over pay, pensions, jobs and increased workloads.
The general council of the TUC decided to support a call to consider the practicalities of a general strike, which will pile fresh pressure on the coalition in its long-running conflict with millions of public sector workers.
A motion to the TUC Congress from the Prison Officers Association on "far reaching" campaigns, including the prospect of a general strike, is expected to be backed by a majority of delegates.
The Brighton conference has voted in favour of co-ordinating action to win concessions from ministers. A number of union leaders raised the threat of civil disobedience.
TUC leader Brendan Barber said the country needs an Olympic-style national crusade to climb out of recession instead of "muddling through". The general secretary told Congress that lessons should be learned from the Olympics on how to rebuild the economy. In his final speech to Congress before stepping down at the end of the year, he said that the lessons of this summer are that the private sector is not always best and that the market does not always deliver.