More than 1,000 Passport Office workers will go on strike for five weeks over a dispute about jobs, pay and conditions.
Members of the Public and Commercial Services (PCS) union working across England, Scotland and Wales will take part in the action from 3 April to 5 May.
Those working in Belfast are being balloted and could join the strike.
The union warned the action is likely to have a “significant impact” on the delivery of passports ahead of summer.
More than 4,000 people are employed by the Passport Office across the UK, meaning around one in four workers will be walking out.
The offices affected in England, Scotland and Wales will include Durham, Glasgow, Liverpool, London, Newport, Peterborough and Southport
PCS general secretary Mark Serwotka said the dispute was over an imposed 2% pay rise not being increased any further by the government.
He added the strike action had come about because “ministers have failed to hold any meaningful talks with us, despite two massive strikes and sustained, targeted action lasting six months”.
He said: “Their approach is further evidence they’re treating their own workforce worse than anyone else.
“They’ve had six months to resolve this dispute but for six months have refused to improve their 2% imposed pay rise, and failed to address our members’ other issues of concern.”
He went on to say that the government was “ignoring our members” over their pay concerns but this would not make them “go away”.
Mr Serwotka said: “But how can our members ignore the cost-of-living crisis when 40,000 civil servants are using foodbanks and 45,000 of them are claiming the benefits they administer themselves?
“It’s a national scandal and a stain on this government’s reputation that so many of its own workforce are living in poverty.”
BBC News has contacted the Home Office for a response.
The latest action from passport office workers comes after months of strikes over pay disputes in other sectors, such as rail workers, London Underground drivers, teachers, NHS staff, regional BBC journalists, university lecturers and civil servants.
On Thursday, unions representing healthcare workers in England agreed a final pay offer with the government – which if accepted by members at a vote would bring walkouts from nurses, ambulance crews, paramedics, hospital porters and other health workers to an end.
A statement released by the government and healthcare unions said both sides believed the offer represented a “fair and reasonable settlement”.
The agreement does not apply to junior doctors as they are involved in a separate dispute with the government.
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