Travellers could face months of disruption unless the Government makes an improved pay offer, the leader of striking Border Force staff has warned.
Public and Commercial Services (PCS) union general secretary Mark Serwotka predicted there would be a “huge escalation” in industrial action in January across the civil service unless ministers enter into negotiations.
Around 1,000 PCS members employed by the Home Office to operate passport booths walked out on Friday at Heathrow, Birmingham, Cardiff, Gatwick, Glasgow and Manchester airports, as well as the Port of Newhaven in East Sussex.
The Border Force strikes will take place every day for the rest of the year, except December 27.
Mr Serwotka said he hoped the Government will “do the right thing and get around the negotiating table and put some money upfront”.
READ MORE: ScotRail warns of severely limited services over Christmas due to strikes
He told BBC Radio 4’s Today programme: “We are raising money, we have a strike fund that means we can sustain this action.
“Our strike mandate lasts right up until May. We will be supporting this action up to May and we would re-ballot again if we have to.
“I think in January what you will see is a huge escalation of this action in the civil service and across the rest of our economy unless the Government get around the negotiating table.”
About 250,000 passengers were due to arrive on flights at affected airports on Friday.
Travellers were warned by Border Force bosses to expect delays amid fears long queues at passport control could lead to people being held on planes, disrupting subsequent departures.
But the deployment of military personnel to check passports ensured passengers did not appear to be delayed on the first day of the strikes.
Defence Secretary Ben Wallace announced that members of the armed forces will receive an extra £20 for each day spent training or deployed to provide cover for industrial action during the festive period.
More than 1,000 personnel from across the Navy, Army and RAF have received training in recent weeks for roles such as passport checking and ambulance driving.
Meanwhile, postal deliveries and driving lessons are set to be disrupted by strikes in the days before Christmas.
Royal Mail, National Highways and Driver and Vehicle Standards Agency (DVSA) employees are taking industrial action on Friday.
They will continue their strike into Saturday, when staff represented by the Rail, Maritime and Transport (RMT) union, Abellio London bus workers and Environment Agency workers will launch separate waves of action.
This follows two days of strikes by NHS staff, with thousands of nurses walking out on Tuesday and ambulance workers joining picket lines on Wednesday.
Prime Minister Rishi Sunak said he is “sad and disappointed about the disruption that is being caused to so many people’s lives, particularly at Christmas time”.
He went on: “When it comes to the difficult question of setting public pay, the Government has acted fairly and reasonably in accepting all the recommendations of the public sector pay review bodies.”
National Highways workers responsible for motorways and major A-roads in London and the South East, also represented by the PCS, will continue their four-day walkout, which started on Thursday.
Postal workers represented by the Communication Workers Union walked out for their fifth day of December action in a move Royal Mail criticised as “a cynical attempt to hold Christmas to ransom”.
The company said it will be doing all it can to deliver Christmas mail, saying the industrial action has cost it £100 million.
RMT railway workers will stage another strike from 6pm on Christmas Eve, which could prevent people from making it home for Christmas.