Thousands of Ryanair passengers could face disruption as a two-day strike by UK pilots gets under way.
On Wednesday, the airline lost a legal challenge in the High Court to block the strike, which is part of a dispute over pay and conditions.
Ryanair has said it will aim to minimise disruption for passengers and will be able to run its “full schedule of flights”.
However, it said it could not rule out some delays.
The airline said it had drafted in pilots from elsewhere in Europe to fill in during strike action.
Ryanair said it would inform passengers of any changes to their flights by email and text message. “If you have not received any SMS or email from us, your flight is scheduled to operate,” it said. Customers can also check its website, it said.
Another 48-hour walkout is planned by the union to coincide with the end of the summer holidays.
On Wednesday, Ryanair won a legal challenge to stop its Ireland-based pilots from striking, but more of its pilots fly from the UK.
In early August, Ryanair’s pilots in the UK joined pilots in Ireland in voting to strike over pay and conditions.
The British Airline Pilots Association (Balpa) announced two 48-hour walkouts, one from 22-23 August and another from 2-4 September.
But Ryanair turned to the courts in London and Dublin in an attempt to block the industrial action, prompting Balpa to accuse the airline of “bully boy” tactics.