Union anger over the Government's austerity drive has been dramatically stepped up with calls for a general strike to show that workers are fighting back like "roaring lions".
The TUC conference supported a move to consider the practicalities of a walkout by millions of workers as part of co-ordinated action against the coalition's policies.
Officials made it clear that the decision did not mean that a mass strike was imminent, but should be seriously considered.
Steve Turner, executive policy director of Unite, told the Brighton conference: "We are at our best fighting back, roaring like lions, not cowering in corners."
Unions are gearing up for a fresh wave of industrial action in the coming months over the Government's austerity measures, including job, pay and pension cuts.
Labour's shadow chancellor stood his ground over the need for pay restraint in the public sector when he addressed delegates.
Ed Balls received polite applause after attacking the Government's "failed" economic policies and calling for alternatives, but it turned to heckling when he made it clear he would not change his mind on public sector pay despite sparking anger last year by supporting restraint.
Delegates later held a fiery debate over how to respond to the Government's "damaging" austerity measures and approved a motion calling for "far reaching campaigns, including the consideration and practicalities of a general strike."
Steve Gillan, leader of the Prison Officers Association, which proposed the idea, said there had to be a "robust" response, adding: "It does not mean we will have a general strike tomorrow, but we should have that in our armoury, because this Government is not afraid or embarrassed to do what it is doing to society.
"We need to make up our mind which direction we are going in, and we should not be afraid to mention the words general strike."