Britain's Queen Elizabeth II has threatened staff at Buckingham Palace that she will deduct the wages of those staff that would join the nationwide strike action.
The warning came after trade unions ordered 140 administrative and reception staff to walk out their jobs in a show of solidarity with other public sector workers, who are protesting at the coalition government's plans to reform their pensions.
The Queen vowed to dock the pay of striking servants, both the administrative and reception staff, at Buckingham Palace and other royal residences.
The Palace staff had been told to walk out by Britain's biggest civil service union, the Public and Commercial Services (PSC) Union.
"They were balloted. So we certainly expect them to walk out," said Richard Simcox, for the PCS.
Other staff among the Royal Household's 1,200 employees are members of Unison and the First Division Association.
"We would not pay employees who do not attend work unless they are sick or on agreed leave arrangements," said a spokeswoman for the Queen.
The strike is the biggest test so far for the Prime Minister David Cameron's Conservative-Liberal Democrat coalition government, which sparked the unions' fury by making public sector workers pay more into their pensions and work longer.