The two-day strike called by the air traffic controllers union in France resulted in flight delays and cancellations on Wednesday, the first day of the strike, officials said.
In the two major Paris airports, Roissy-Charles de Gaulle and Orly, there were delays and cancellations during the early morning, a warning about which was issued on Tuesday by the Directorate General of Civil Aviation (DGCA), Efe news agency reported.
The agency announced that 40 percent of the scheduled flights would be suspended in anticipation of the strike, while passengers were warned in advance of flight cancellations to avoid long lines at the airports.
The DGCA will announce on Wednesday night its flight cancellation forecast for the second day of the strike.
The main air traffic controllers union called for the two-day strike to demand immediate negotiations on the rules of labour organisation.
Transport Minister Alain Vidiales regretted the call for the strike at a moment when, he said, negotiations had already begun.