Thousands of air passengers face disruption due to a three-day strike by air traffic controllers in France which started today.
The workers are protesting against an EU plan to create a single European airspace, which they say would affect their working conditions and public safety.
According to Ryanair the strikes will result in 102 of their flights to and from France being cancelled today, with more flights entering French air space at risk of disruption.
A total of six Aer Lingus flights have been cancelled today.
Ryanair spokesman Robin Kiely said it was unacceptable that strikes were taking place already in the peak of summer season.
"It is unacceptable that the skies over Europe are repeatedly closed or flights are delayed by the unjustified strike action of tiny numbers of air traffic controllers.
These public servants are among the most overpaid and protected in Europe and yet they repeatedly opt for the strike weapon as a first, rather than a last resort,” he said.
"The solution to this problem is simple: remove their right to strike in exactly the same way that Air Traffic Controllers in the USA are prevented by law from striking. Until then, it is up to the EU Commission and French Government to ensure there are no further cancellations on Wednesday and Thursday as a result of these unwarranted strikes."
Passengers affected by these strikes are advised to contact their airline.