French air traffic controllers intensified their strike Wednesday, with around half of all flights in and out of the country set to be grounded over EU plans to centralize control of the bloc's airspace, DPA reported. Some 1,800 flights were cancelled on Wednesday, according to French civil aviation authority DGAC. As many flights had to be cancelled on Tuesday, the first day of the protest. The disruption has affected short- and medium-haul flights particularly, with Air France saying its long-haul services were operating as usual. German carrier Lufthansa listed 51 cancelled flights on its website. On top of flights to and from Paris, Marseille, Lyon, Nice and Toulouse, some flights from Germany to Spain and Italy and within Germany were also affected. The strike was set to end on Thursday at 0400 GMT.