Fraport, the company that operates Europe's third largest air traffic hub, has advised travelers to check with their airlines to see if specific flights from Frankfurt airport have been cancelled on Friday due to a strike by tarmac workers.

On Thursday, 173 flights were cancelled due to the strike action, which began in the afternoon. The number of affected flights was higher on Friday since the strike began at 8 a.m. and was to continue throughout the day, until 10 p.m.

Germany's flagship carrier, Lufthansa, alone cancelled 250 flights on Friday, most of them within Europe.

Replacement workers were able to keep some flights on schedule on Thursday.

Wage dispute

The 200 air-traffic controllers and workers on strike are known as "apron control" staff. They direct planes in and out of their parking positions. They walked off the job to back up their demands for higher pay and improved working conditions.

The German union for air traffic workers, GdF (Gewerkschaft der Flugsicherung), opted for the strike action after management turned down mediation proposals in the wage dispute.

Fraport's executive board member for labor relations, Herbert Mai, said GdF's expectations were far too high.

"The union remains completely intransigent and irresponsible in its demands for high, double-digit pay increases and other adjustments for working hours and special benefits ranging between 50 and 70 percent," Mai said on Wednesday. "We regret that GdF's rigid position has been taken at the expense of the passengers, airlines and employees. We remain committed to our offer and to resuming talks, as long as GdF is willing to engage in realistic negotiations."

mz/slk (dpa, dapd)