STUTTGART/HAMBURG (REUTERS) - Almost 100,000 metal and electrical workers went on strike across Germany on Tuesday as they sought to put pressure on their employers to increase a pay offer, engineering union IG Metall said.

The union is calling for wage hikes of up to 5.5 per cent for some 3.7 million workers from May. It has so far rejected an offer from employers to increase wages by 2.3 per cent from July following two months without a raise.

IG Metall and employers are due to start a third round of negotiations in Baden-Wuerttemberg on Tuesday. Any agreement reached in the state home to major carmakers such as Daimler and Porsche would set the tone for wage hikes in the engineering sector nationwide.

Negotiations are due to restart in the southeastern state of Bavaria, where BMW has its headquarters, on Wednesday.

Negotiations take place at a regional level before a deal made in one region is deemed a pilot agreement and generally adopted by the other regions.

IG Metall head Berthold Huber said: "We only have just under 10 days left to reach an outcome at the negotiating table."

The union wants to vote on an unlimited strike if no agreement is reached by the Whitsun holiday, which takes place on May 19-20. An agreement is not expected this week. Further strikes are planned for Wednesday in Baden-Wuerttemberg, Bavaria and North Rhine-Westphalia.

German unions are pushing for inflation-beating wage hikes this year, confident politicians courting votes for a federal election due in September will back their demands.

According to preliminary figures, annual inflation was running at 1.2 per cent in April.