The prospect of a walkout by hundreds of thousands of teachers, civil servants and other public sector workers is set to come a step nearer this week when the results of ballots for strike action are announced.
Members of three unions have been voting on whether to take joint action, expected to be held on June 30, in protest at cuts in jobs and pensions and a pay freeze.
Up to 750,000 workers could be involved in the strike, making it the biggest day of industrial unrest for years and setting the Government on a fresh collision course with public sector workers.
Two teaching unions, the Association of Teachers and Lecturers (ATL), and the National Union of Teachers (NUT), will announce the results of their ballots on Tuesday.
They are concerned at moves which they say will see them working longer, paying more and receiving less when they retire.
ATL, seen as the most moderate teaching union, has never taken national strike action before.
General secretary Mary Bousted said the response from members has been "overwhelming".
"I've never seen ATL members so angry about what the Government is doing and I've never seen such determination by members to protect their pensions."
A teacher's pension amounts to around £10,000 a year on average, Dr Bousted said, and are not "gold-plated".
"They are a modest return for a lifetime of teaching the nation's children."
NUT general secretary Christine Blower said: "Teachers of all ages are astonished that the Government should be doing this to their pensions."
Between them, the two unions are balloting almost 300,000 members.
The Public and Commercial Services union will announce the result of its ballot on Wednesday, with officials confident of a yes vote.
General secretary Mark Serwotka said: "Our members know that everything they have ever worked for is now under threat, and they are voting to say there is an alternative worth fighting for.
"The Government is seeking to blame and punish public sector workers for an economic crisis that ministers and their advisers know was caused by greed and recklessness in the financial sector.
"This ballot is about showing that, if we invested in our economy and tackled the real scroungers who dodge paying billions of pounds in taxes, we would not need to cut a single penny from public spending."
The union said its members faced job losses, a wage freeze as well as detrimental changes to their pensions.
Other unions have warned of possible industrial action later in the year unless long-running negotiations over public sector pensions can lead to a deal.
The GMB has said it is prepared to ballot its members, including those in local government, if the deadlock is not broken.