Ryanair has cancelled most flights to and from Spain and all Spanish domestic flights due to operate on Wednesday due to a 24-hour strike.
British Airways and easyJet admitted their services to and from Spain would also be badly hit and both airlines are giving passengers the option to cancel or re-schedule their trips without incurring fees.
At least one in five flights is expected to be cancelled and passengers connecting on to long-haul services at Spanish hubs will also be affected.
Ryanair had hoped to operate hand-baggage only flights to Spain during Wednesday in order to reduce the inconvenience and disruption to its passengers, but on Tuesday evening it said this would not be possible.
It accused the Spanish government of failing to guarantee a minimum level of service for non-Spanish airlines during the 24-hour general strike, from midnight on Tuesday.
Ryanair reiterated its call for the European Commission to outlaw strikes by workers providing essential services such as air traffic control.
Airlines have also been forced to cancel flights to and from Belgium on Tuesday and Wednesday due to a wild-cat strike by Belgian air traffic controllers which started on Tuesday lunchtime and is due to end at 1pm Wednesday.
A strike by French air traffic controllers disrupted flights to and from the UK last week.
By Linsey McNeill
