Ryanair cancelled 400 flights throughout Europe on Tuesday amid ongoing strikes by French traffic controllers.
The airline’s chief executive Michael O’Leary said the walkouts had prompted cancellations of around 12 per cent of its planned flights - though none were domestic flights in France.
French air traffic controllers are needed to communicate with aircraft flying over the country’s airspace, meaning that flights from the UK to Spain or Italy - known as overflights - are affected by the walkout.
Mr O’Leary said in a statement: “It's absolutely indefensible that flights going from Ireland to Italy, from Poland to Portugal, or from Spain to Germany are being cancelled simply because the French want to prioritise their domestic flights and cancel all the overflights.
“We respect the right of French air traffic control to strike but it should be French domestic flights or local flights to France that get cancelled.
“The French can take the train, they can take the motorways, but the people flying across France are having their flights unnecessarily cancelled because the European commission led by Ursula von der Leyen will not take action.”
The walkout, over pension reforms proposed by President Emmanuel Macron, began at 6pm on Monday and will last until 6am on Wednesday.
Mr Macron’s reforms would see the retirement age in France increased from 62 to 64 years. The move has sparked furious protests throughout France since January.
Meanwhile, France’s civil aviation authority has instructed airlines to cancel up to a third of flights on strike days at certain airports.
Disruption is expected at Paris’ Orly, Charles de Gaulle and Beauvais airports as well as Marseille, Lyon, Toulouse, Bordeaux and Nice.
Earlier this week, Ryanair hit out at the President of the EU Commission Ursula von der Leyen for not responding to a petition signed by more than a million customers urging her to protect overflights.
Mr O’Leary said: “Europe is a single market. In a single market the overflights and skies over Europe must be protected. Take action.”
Greece, Italy and Spain all protect overflights regardless of industrial action.
