Co-ordinated public sector strike action, set to begin on the 30 June, looked more likely today as PCS union members of the civil service were expected to vote for industrial action.

PCS, which could call 300,000 workers out on strike, said employees were angry about forced pension changes, job cuts and wage freezes as the government cuts sector budgets.

Ballot results will be revealed later today, but PCS general secretary Mark Serwotka said that mass strike action was “inevitable” given the strength of feeling about pension changes alone.

He said: "I don't think it’s surprising that people will want to defend themselves and if you're going to defend yourself it obviously makes sense that you make common cause with council workers, health workers and teachers, because we all face the same attacks."

The pensions shake-up was prompted by Lord Hutton's review published in March, which called for an end to final salary schemes and for pensions to be linked to career average earnings.

This latest potential strike threat follows a vote to walk out by the National Union of Teachers and the Association of Teachers and Lecturers, earlier this week.

Meanwhile, Unison’s general secretary Dave Prentis increased the tension between the unions and government yesterday as he warned that 1.2 million state employees could strike if the row over pensions was not resolved.

However, Cabinet ministers Sir Francis Maude and Vince Cable have counter-warned the unions against mass action, as this could make the case for tougher laws on union walkouts.