Hundreds of contract staff in jobcentres are to go on strike in a dispute over job cuts.
Members of the Public and Commercial Services (PCS) Union working in call centres, jobcentres and offices across the country will walk out for two hours.
They are employed by Balfour Beatty, providing the Department for Work and Pensions with telephone and typing services.
PCS general secretary Mark Serwotka said: "This dispute is a result of privatisation creating a two tier workforce.
"Balfour Beatty staff work alongside civil servants but are treated much worse.
"There has been no attempt to redeploy people facing redundancy and the terms on offer are the lowest the company can get away with and stay within the law."