A two-day strike by airport workers, called by the Verdi trade union in a public sector wage dispute, has begun at Munich Airport.
Airlines have canceled 80% of scheduled flights for Thursday and Friday, the airport operator FMG said on its website.
Further cancellations could not be ruled out, the airport said in a statement.
At Munich Airport, 830 takeoffs and landings were originally scheduled over the two days, but with 80% canceled, more than 1,300 flights will be affected.
The airport in the south of Germany is among the country's largest and is used as a secondary hub for the Frankfurt-based German flagship airline Lufthansa.
A parallel strike at Hamburg Airport will also cause disruptions on Thursday and Friday. Verdi said on Wednesday that airport workers, including maintenance staff, IT services, airport security, and baggage transport staff, would join the strike.
The strike is set to end at midnight on Friday.
Lufthansa has pledged to assist affected passengers with free rebooking or cancellations.
The strike comes amid collective bargaining negotiations between public sector workers and local authorities.
Verdi demands an 8% wage increase and better working conditions, including three additional days of paid leave.
Airlines are not part of the negotiations, but they are caught in the fallout.
