Senior union leaders have predicted a surge in strike action for 2011 on a scale not seen since the campaign to abolish the poll tax.
Mark Serwotka, the leader of the Public and Commercial Services Union, said strikes in the spring were "inevitable" and could affect the royal wedding between Prince William and Kate Middleton.
TUC general secretary Brendan Barber said it was going to be a "horrible" year, with cuts in benefits and public services and an increase in unemployment.
And RMT general secretary Bob Crow said the "fightback" against cuts would see public and private sector workers take to the picket lines.
Mr Serwotka told The Times: "Strikes are inevitable. We are looking at the spring. The more of us that stand together against the cuts, the more problems we can create. Unless you look like you want a fight, they won't negotiate. The Government has to see we are serious."
He said the unions would not specifically target the royal wedding at the end of April but added: "Actions around Easter have quite an effect because so much is happening at that time of year. The end of April, beginning of May would be best. The royal wedding would not be a factor in our planning but nor would it be a factor to avoid."
A PCS spokesman said it was a mere coincidence if the strikes were timed to occur around the time of the royal wedding.
He said: "We are opposed to cuts to public sector pensions. Any strike over public sector pensions is designed to force the Government to withdraw any plans it has to devalue pensions."
In his New Year message, Mr Barber said: "It's hard to pick out the unkindest cut of all, but a top contender must be the 10% cut in housing benefit that kicks in after someone has been unemployed for more than a year."
The TUC leader warned that the Government could also have a horrible year, predicting growing anger about increased student tuition fees and cutbacks in public sector projects such as new schools.
"What is becoming clear to people is just how unfair the coalition's policies are. Those who did least to cause the crash are being made to take the nastiest medicine with the worst side-effects."