GMB warns of civil disobedience if strike rights go
The GMB has threatened a huge civil disobedience campaign if the government tries to change the rules on striking.
The union's general secretary told its conference that any change to the right to strike would be fiercely resisted.
Paul Kenny gave the warning after the Business Secretary Vince Cable told delegates that calls to change strike laws would grow louder if there was widespread industrial action.
Unions plan mass protests against the government's cost-saving measures.
Speaking at the GMB's annual gathering in Brighton, Mr Kenny said: "Cameron and Clegg and the other fella, I promise you this. You try to stifle the basic rights of working people to go on strike and we will give you the biggest civil disobedience campaign your tiny little minds have dreamt of."
Delegates gave Mr Kenny a standing ovation.
The 700,000-member GMB union represents workers across all industries in both the private and public sectors.
Unions are planning to stage a co-ordinated day of strikes and other protest action on June 30 against the government's spending cuts.
Mr Cable was booed and heckled on Monday after he said that the pressure on him to act to make it tougher for people to take industrial action would "ratchet up" if there was widespread disruption.
But he added that if the level of strikes remained low there would not be a compelling case for tighter laws.
There are strict rules in place for workers planning mass protests, including procedures for balloting and a timetable within which any agreed action can take place.