Tens of thousands of holidaymakers were facing fresh travel chaos on Friday as a French air traffic control strike gets under way.
The walkout forced major airlines to cancel flights due to limits on flying over France, including Ryanair which has axed 420 flights, affecting some 80,000 people.
EasyJet is cancelling 76 flights, British Airways cancelling 22, and Air France said it could only run 45% of its short-haul flights.
In a statement, Ryanair’s Operations Director Neal McMahon said: “It is inexcusable that passengers who are not even flying to or from France are disrupted.”
Mr McMahon said French laws protect French domestic flights, but not ones flying over the country.
“It is time that the European Union step in and protect overflights so that European passengers are not repeatedly held to ransom by a tiny French air traffic control union," he said.
He called for other air traffic control centres to be allowed to manage overflights of France during strikes.
Rival EasyJet said it had cancelled flights after being asked to do so by French authorities.
EasyJet said: “While this is outside of our control, we would like to apologise to our customers for any inconvenience they may experience."
France's civil aviation authority earlier this week asked airlines to halve their flight schedules on Friday due to the planned strike.
The SNCTA air control union has cited inflation and a lack of recruitment as the reasons for the walkout.
“Between 2029 and 2035, one third of the [air traffic control] workforce is retiring. It is imperative that we anticipate and plan recruitment,” the union said.
“If not, the consequences will be inevitable in terms of the public service, working conditions and flexibility.”
The SNTCA said it was also planning a second strike from September 28-30 if an agreement is not reached.