The workers began a two-day walkout on Tuesday over plans by the British government to axe 30,000 jobs in the Department for Work and Pensions (DWP).
“We are arguing that they should halt the job cuts and take a look at what is happening to services as a result,” a union spokesman told AFP, adding that some 17,000 positions have been cut already.
However, he denied that the strike was timed for maximum impact, with Mr Blair’s Labour Party bracing for a drubbing in the local council elections in England as crises engulf key cabinet ministers.
Mr Blair has conceded that life was “especially difficult” after nine years in power as his scandal-hit Labour Party faced the prospect of heavy losses on Thursday.
Meanwhile union leaders have hailed Tuesday’s strike as “a fantastic turnout right across England, Scotland and Wales”.
Job centres and welfare offices across Britain were hit by the strike, including those in London, Birmingham, Cardiff and the Scottish Highlands, the union said.
The striking civil servants, who are all members of the Commercial Service Union, comprised around two-thirds of the total DWP workforce, according to the spokesman.
Tuesday’s walkout followed the collapse of talks and came after a similar two-day stoppage in January earlier this year.
Election under scrutiny
Thursday’s local elections in England will be scrutinised more than usual as they will be not only a test for the new opposition party leaders but also for Prime Minister Tony Blair’s embattled Labour Party.
Both David Cameron, of the main opposition Conservatives, and the Liberal Democrats’ Menzies Campbell will be hoping to snatch support from Labour, which has been rocked in recent weeks by one crisis after another.
About 23 million voters are eligible to vote in the elections which see 4,360 of the 19,500 English local authority seats up for grabs.
Turn-out is traditionally low but the stakes this time round are high: a significant electoral defeat for Labour, the loss of 200-plus seats, could have national repercussions.
It could lead to a widespread government reshuffle, including some of the most senior figures in Mr Blair’s Cabinet inner circle, and force Blair into declaring his hand over when exactly he will step down from office.
Significant attention is on London where seats are being contested on all 32 boroughs that make up the British capital. Analysts suggest Labour could lose three or four of the 15 councils it currently controls.
Here, and in Britain’s multi-cultural second city of Birmingham, there are concerns that the extreme-right British National Party (BNP) could make significant gains. Its anti-immigration policies have been closely followed.