Thousands of civil servants employed by the Ministry of Defence (MoD) and the Identity and Passports Service (IPS) are staging a one-day national strike over a below-inflation pay rise.
Around 20,000 public sector workers are expected to join the industrial action, while fellow members of the Public and Commercial Services Union (PCS) will be indirectly supporting the strike by refusing to work overtime and taking full rest and lunch breaks.
Today's strike forms part of a month-long protest campaign by civil servants over Gordon Brown's announcement earlier this month that he had accepted recommendations from the pay review body to peg public sector wage rises below the government's 1.9 per cent target for inflation.
Workers from other government departments, including the Crown Prosecution Service (CPS) and the Department of Health (DoH), will also be campaigning against the proposed pay award in coming weeks, the PCS said.
Commenting on today's strike, PCS general secretary Mark Serwotka said: "Battered by massive job cuts and privatisation, dedicated staff across the civil service have become increasingly angry about the government using their pay as an anti-inflationary measure."
But the chancellor has continued to insist that the move is necessary on order to keep inflation under control and prevent a return to "boom and bust".
Explaining his decision to keep civil servants' wages capped below inflation during last week's Budget, Mr Brown told the Commons: "Holding firm to our commitment to maintain discipline in public sector pay, we will not only secure our two per cent inflation target but create the conditions for maintaining the low interest and mortgage rates that since 1997 have been half the 11 per cent average of the previous 20 years."