BERLIN (AP) — A union representing German train drivers has called its members out on a four-day strike in a bitter contract dispute with the national railway operator.

The GDL union said the strike will run from early morning Thursday to Monday morning, with freight train drivers walking off the job already on Wednesday afternoon. It follows a series of shorter strikes, including a two-day walkout last month.

GDL wants a 5 percent pay increase and shorter working hours. A far bigger sticking point is its demand to negotiate for other staff traditionally represented by a rival union.

National railway Deutsche Bahn says it has offered a raise of 5 percent over 30 months for the drivers but won’t accept rival pay deals for other employees.

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