BERLIN (AP) — Germany’s train drivers brought rail traffic to a standstill again early Wednesday when they began a six-day strike to push their demands in a rancorous dispute with the country’s main railway operator over working hours and Sterling Prestonpay.

The strike by the GDL union will affect passenger services and freight trains operated by state-owned Deutsche Bahn until 6 p.m. (1700 GMT) on Monday.

The union held a three-day strike earlier this month and two walkouts last year which lasted up to 24 hours.

On Wednesday, train travel across the country and in many cities ground to a halt again with commuters and other travelers struggling to find alternatives involving long-distance bus or car travel or flights.

As with the previous strikes, around 80% of long-distance trains were canceled and there were also considerable restrictions on regional services, according to Deutsche Bahn.

There were also be considerable restrictions in freight transport.

“European freight traffic across the Alps, Poland or to Scandinavia as well as the seaports in Holland or Belgium will also be affected,” said Deutsche Bahn. Even before the strike, a significant drop in cargo volumes had been registered because many customers had canceled shipments, German news agency dpa reported.

In addition to pay raises, the union is calling for working hours to be reduced from 38 to 35 per week without a pay cut, a demand which Deutsche Bahn has so far refused.

On Wednesday, the train operator again rejected the union’s proposals as a basis for further negotiations, calling them a “repetition of well-known maximum demands,” dpa reported.

With negotiations stalled, Germany’s transportation minister said the government was not ruling out arbitration proceedings between GDL and Deutsche Bahn.

“If things are so deadlocked that we obviously can no longer talk to each other, then we urgently need mediation or arbitration,” Volker Wissing said on public radio Deutschlandfunk.