British Airways will cancel around 32 flights per day to and from Heathrow over the Easter weekend due to a strike by security guards at the airport.
Members of the Unite union will walk out for 10 days from Friday in a dispute over pay after talks to avert the action failed last week.
Heathrow said it was putting “contingency plans” in place and drafting 1,000 extra staff – as well as its management team – into terminals to help passengers during the Easter getaway.
“We’ve apologised to customers whose travel plans have been affected and have offered them a range of options, including rebooking on to a new flight with us or another airline, or requesting a full refund.
“Our teams are continuing to work closely with Heathrow to ensure that our customers’ journeys run smoothly.”
British Airways has cancelled around 5% of its flights during the industrial action and stopped selling tickets for strike days. The cancellations fall on short-haul routes and the long-haul services are not affected.
A Heathrow spokesman said: “We will not let these unnecessary strikes impact the hard-earned holidays of our passengers.
“Our contingency plans will keep the airport operating as normal throughout.
“We are deploying 1,000 additional colleagues and the entire management team, who will be in the terminals providing assistance to passengers over the busy Easter getaway.
“As at any busy time, it may take a little longer than usual to get through security, but this will be well-managed and kept flowing.
“Passengers can help us ensure they get the best start to their journeys by checking their flight status with their airline before travelling to the airport, arriving at Heathrow no earlier than two hours before short-haul flights and three hours before long-haul flights, and by being ready for security with their compliant liquids and electronics out of their hand luggage.”