Civil Servants in Leicestershire and Somerset have joined the two-day strike called today by the Public and Commercial Services union in response to plans by the government to cut redundancy payments.
As more and more regions joined the protest a spokesman claimed that the "vast majority" of its members will support the walkout.
Up to 270,000 civil servants are expected to join the protest nationwide that threatens to cause disruption in government regional offices, jobcentres, courts, call centres and Whitehall departments. The strike is also expected to affect parliament, where House of Commons security staff are due to stop work for the first time in 25 years.
Mark Serwotka, the union's general secretary, said there was "incredible anger" about the proposed changes. Membership had grown since the strikes were announced last month, he said.
"Civil servants face losing up to a third of their entitlements and tens of thousands of pounds if they are forced out of their job. The government is tearing up the contracts of low-paid civil and public servants whilst it claims it can do nothing about bankers' bonuses because of contractual obligations," he said.
The government has spent 18 months negotiating the changes, which will cap redundancy payments for those earning more than £30,000 a year at twice their annual salary. Five other civil service unions have accepted the deal, which will save £500m over three years.
Tessa Jowell, the Cabinet Office minister, said the government had already agreed that civil servants earning less than £30,000 – 80% of the total – will still qualify for redundancy worth up to three years' salary. "This package brings the civil service more into line with the rest of the public sector and still offers more generous terms than much of the private sector," she said.