Local buses, trams and subway trains were cancelled in much of Germany on Friday as transport employees walked off the job in the country’s third transport-related strike in two weeks.

The Ver.di service workers’ union called for a “warning strike”, a common tactic in German contract negotiations, on Monday.

Its deputy leader, Christine Behle, said that “the time has now come to exert more pressure on employers” as talks on new pay contracts for about 90,000 people employed by over 130 local transport operators have failed to make progress.

The exact demands and the length of Friday’s walkouts varied from place to place.

In Berlin, workers with the local transport authority walked off the job until 10am; in Hamburg, Cologne, Hannover and elsewhere, the strike was to last all day.

Bavaria, where there are no negotiations at present, was the only region not affected.

The dispute centres on demands for better working conditions, such as a shorter working week and extra compensation days for shift and night work.

Coinciding contract negotiations in the rail, airport and local transport sectors have made for a frustrating few weeks for German travers and commuters.

The German railway system is involved in a separate dispute that centres on a train drivers’ union’s demand for a shorter working week.

In an unrelated dispute that centres on pay demands, Ver.di on Thursday called security workers at most of Germany’s major airports out on a one-day strike that prompted widespread flight cancellations.