BERLIN - Germany's largest industrial union, IG Metall, staged walkouts across Germany on Thursday and called for mass stoppages in coming days to intensify pressure on employers in a row over pay and working hours.
IG Metall in the state of Baden-Wuerttemberg, which traditionally leads pay negotiations for the rest of Germany, asked 51,000 engineering workers to stage walkouts of up to three hours on Friday.
"These stoppages...should also carry on into next week," the union said in a statement.
It said Friday's action would affect Audi and auto components group Kolbenschmidt Pierburg.
Several thousand IG Metall members had already staged brief walkouts at factories across Germany during night shifts and morning shifts after an "industrial peace" period requiring it not to strike expired on Wednesday at 2300 GMT.
The walkouts come after talks were adjourned when IG Metall said it could not accept employer demands for longer working hours and an offer for less than half the 4 percent pay rise it is demanding for 3.5 million engineering workers.
Among the firms hit overnight was DaimlerChrysler AG, whose workers downed tools in several plants.
A spokeswoman for DaimlerChrysler said: "We think warning strikes send the wrong signal. They lead to completely unnecessary economic damage and endanger the competitiveness of the entire industry."
But striking workers standing in the snow outside the firm's Mercedes factory in southern Berlin said the strikes were important to show how much power the union has.
"What employers have offered us is a huge provocation. We want to make them come to the negotiating table with a reasonable offer," said 50-year-old machine operator Ali Erdogmus. "You can see today how strong the union is."
He said 1,000 workers walked out at the plant for almost two hours. "It is completely empty right now," he shouted over the strikers' horns, rattles and whistles.
Wage talks were adjourned this week after employers offered IG Metall two pay rises of 1.2 percent over 27 months and asked unions to make contracts with employers more flexible so firms can vary working hours to match demand.
The union says such flexibility could result in an increase in working hours which could cause thousands of job losses and could equate to an effective pay freeze or cut if there is no accompanying wage rise.
The next round of wage talks in Baden-Wuerttemberg, where both Porsche and DaimlerChrysler are based, is scheduled for Feb. 5.