UK Border Force staff will hold industrial action from Friday, December 23 to Monday, December 26 and Wednesday, December 28 to Saturday, December 31.
Heathrow, Gatwick, Glasgow, Manchester, Birmingham and Cardiff airports will be affected. Staff at the port of Newhaven in southern England will also walk off the job.
British government officials said armed forces personnel and public servants have been trained to check passports when Border Force begin striking.
“We apologise for any disruption caused to travellers entering the UK,” Border Force CEO Steve Dann said.
“We are working together with partners across the travel industry to ensure we can continue to meet critical demand and support the flow of passengers and goods through our border.
He urged passengers to contact their airlines or travel company to check that their flights are running as planned.
UK Home Secretary Suella Braverman warned of “undeniable, serious disruption” because of the strikes and urged anyone flying to rethink their travel plans over the holidays.
But there are concerns that delays in checking the passports of arriving passengers could spark long queues and even travellers being held on aircraft, impacting subsequent departures.
”It could go really, really badly,” said UK travel expert Rhys Jones.
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Delays getting through the border could lead to overcrowding in the terminal, meaning that airplanes could be asked to keep passengers onboard – leading outgoing flights to be delayed, too.
From then, it’s a snowball effect.
“Aviation works on planes being in the right place at the right time,” Jones said.
“If aircraft are out of position, all of a sudden you have a massive network crisis.”
Airlines have not cancelled flights so far, and anyone with a biometric passport can use the e-gates.
“The main bottleneck will be where you have to see an officer,” Jones said.
The airport strikes are just one industrial action besetting the UK over the Christmas period as public sector workers press for pay increases to keep up with the inflation rate of 11 per cent.
Strikes have been called for nearly every day of December: for nurses (their first ever strike), health workers, ambulance drivers, postal workers, driving examiners, bus drivers, rail workers, highways workers, baggage handlers and Border Force.
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