European flights faced widespread disruption on Friday as a strike by French air traffic controllers forced airlines to cancel half of those scheduled to arrive or depart airports in Paris and others that were due to have flown over France.

Strikes and staff shortages in the past few months have forced airlines to cancel thousands of flights, dashing their hopes of a summer rebound after widespread COVID-19 lockdowns, with disruption continuing into the autumn.

"It is inexplicable that thousands of European citizens/visitors will have their travel plans unfairly disrupted by yet another French ATC (air traffic control) strike," Ryanair said.

French air traffic control union SNCTA said in a statement that the walkout by its members was over the effects of inflation and its demand for more staff members.

Ryanair said the travel plans of 80,000 passengers had been affected when it had cancelled 420 flights, mainly intended to fly over France.

Air France had said on Wednesday that it would operate only 45% of its short and medium-range flights and 90% of its long-haul flights.

Aviation authority DGAC, which had asked airlines to halve their flight schedules, said some local airports were temporarily closed, including Montpellier and Rennes, adding there were "significant delays" across the country's airports.

"Everything is very quiet, as the passengers had been warned in advance and did not go to the airports," a spokesperson for Paris airports operator Groupe ADP told Reuters.

Airlines had tended to cut short and medium services rather than long ones, the spokesperson added.

Low-cost carrier EasyJet said it had cancelled 76 flights due to the strike.

Major airports in neighbouring countries also felt the impact, with Spanish airport operator AENA saying the strike had forced it to cancel 65 flights. (Reporting by Benoit Van Overstraeten in Paris, Emma Pinedo in Madrid, Padraic Halpin in Dublin and Yadarisa Shabong; Editing by Ingrid Melander, Bradley Perrett and Alexander Smith)