50,000 have flights cancelled by Ryanair
More than 50,000 passengers booked on peak summer holiday flights have been told their trips have been cancelled.
Ryanair has cancelled "up to 300" flights in response to coordinated 48-hour strikes by cabin crew in Belgium, Portugal and Spain next Wednesday and Thursday.
The staff are unhappy about a range of pay and conditions issues.
Most of the cancelled flights are to, from and within Spain, where around a quarter of the airline's 830 daily services have been grounded.
Up to 50 flights starting or ending in Portugal and Belgium have been cancelled.
The airline said: "All affected customers have been offered re-accommodation on alternative flights during the seven days prior to 25/26 July, or the seven days after.
"Alternatively, these customers can obtain a full refund of their airfares."
Passengers whose flights are cancelled while they are on holiday are entitled to hotels and meals until the airline can get them home. If no Ryanair flight is available on the intended day of travel or the next day, the airline must buy a ticket on another carrier, if there is space available.
The firm announced in December that it would recognise trade unions.
Pilots employed by Ryanair in Dublin are striking tomorrow, one of the busiest days of the summer.
Around 4,000 passengers have been affected by the cancellation of 24 flights. A further pilots' strike is scheduled for Tuesday.