Hundreds of workers at German carmaker Daimler went on strike on Wednesday, engineering trade union IG Metall said, after wage talks affecting 70,000 employees in the state of North Rhine-Westphalia stalled last week.
Daimler's Sprinter plant in Duesseldorf was hit by the walk out during the early morning shift as 800 workers downed tools, starting a wave of warning strikes planned for Germany's industrial heartland, IG Metall said.
"Our patience is at an end, we want a 6.5 percent wage increase," Oliver Burkhard, a regional union leader, said in a statement.
"If employers don't get moving, then today's warning strikes will be just the beginning. We're ready for a fight," he said.
Years of wage restraint have boosted Germany's competitiveness and helped to cut its unemployment rate to a two-decade low.
Wage rises in many other euro zone countries have been steeper than in Germany in recent years, fuelling the economic divergence which has underpinned the debt crisis in the single currency area.
The wages of around 9 million workers are up for negotiation this year in Europe's largest economy, and deals agreed so far have outstripped inflation.
The powerful IG Metall, one of Germany's largest trade unions, is asking for a 6.5 percent wage increase this year for its 3.6 million members nationwide.
The trade union rejected an offer of 3 percent over 14 months last week from employers in the engineering sector, describing it as a farce.
Further walkouts affecting more than 100 companies are planned for Thursday, the union said.
German public sector union Verdi clinched a wage increase of 6.3 percent over 24 months for two million workers earlier this month in the third round of negotiations, ending a series of warning strikes that had disrupted transport and services.
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