More than 600 Border Force officials at Heathrow Airport will strike for four days in April.
The strike action will take place from 11-14 April, the PCS union announced.
The workers, who carry out immigration controls and passport checks at Heathrow, voted by 90% to walk out over a new roster and imposed changes to shift patterns.
The union said the changes could see 250 staff at the London airport forced to lose their jobs by the end of next month.
Fran Heathcote, general secretary of PCS, said: “Ministers have 14 days to withdraw these unfair and unnecessary proposals or our members at Heathrow will take strike action.
“Consultation with staff has been a farce, with our members having little or no choice about the new arrangements.
“Ripping up flexible working arrangements is no way to treat staff especially, as the government says, their work is critical to our nation’s security.
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“Some members are heartbroken that the Border Force has become ‘unprofessional and inhumane’.
“If the government is serious about border security, it should look at Border Force officers’ job security, look after its staff, scrap the changes and work with us to protect jobs and working conditions.”
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