After a two-day meeting in Detroit, the GM board dispatched company Vice President John Smith to Berlin to tell both the Opel workers and the German government of its decision.

GM's European subsidiary includes Opel's operations in Poland, Spain and Belgium as well as Britain's Vauxhall brand.

The decision to select Magna follows mounting speculation in recent weeks that GM wanted to retain control or a dominant role in Opel because the US carmaker was reluctant to give the Russian interests in the Magna bid access its technology.

But in line with calculations made by Opel's German trade unions, the international financial advisory group KPMG told the GM board in a report it would need up to $6.1 billion to retain its European subsidiary.

However, the final decision on the future ownership structure of Opel rests with a German government-backed trust, which currently oversees the day-to-day affairs of the auto group.

The trust would not be consulted if GM opted to retain control of the Opel.

Plunging car sales resulted in GM launching earlier this year a major restructuring of its global operations, including selling off of a majority stake in Opel.

But since then, the carmaker has emerged from bankruptcy and a new GM board has been appointed. Also, there are signs the economic crisis has abated for the global car industry and the world economy in general.