BERLIN — Berlin’s airport has canceled all of its flights for Monday ahead of a labor union strike that is expected to impact thousands of flights at 11 airports across Germany.

The ver.di union representing airport ground staff announced the strike Friday to give travelers time to prepare. It said workers will walk out at the airports in Munich, Stuttgart, Frankfurt/Main, Cologne/Bonn, Düsseldorf, Dortmund, Hanover, Bremen, Hamburg, Berlin-Brandenburg and Leipzig-Halle.

Hundreds of thousands of travelers could see delays or cancelations of their flights.

The union’s negotiators demand better working conditions, higher wages and additional days off, among other things.

In addition to massive travel disruptions, the strike could also have a major economic impact on hotels, restaurants and retailers, according to airport association ADV.