The country's DGAC civil aviation authority told airlines that they should scrap as many as 50 percent of the 4,000 or so services that begin or end in France on a normal day, up from 40 percent on Wednesday. The walkouts involve members of the SNCTA union who are seeking concessions on issues including retirement age and changes that will come as Europe moves toward a so- called single sky unifying air traffic control.

The French unit of Air France-KLM Group said it plans to operate all long-haul services today, while cutting about half of scheduled medium-haul flights from Charles de Gaulle airport, and three out of four short-haul flights to and from Paris Orly. About 60 percent of Air France services from provincial cities will also depart as usual.

Other airlines serving France have also been affected, including Air France's Dutch sister company KLM. In Germany, Deutsche Lufthansa AG canceled 34 services in and out of France on Thursday.

Low-cost carriers, which run to tighter timetables, are worse hit than network operators. Ryanair Holdings Plc, Europe's leading discount specialist, scrapped 254 services today, bringing the total for the two days to more than 500. EasyJet Plc terminated 226 services, following 118 yesterday.