Berlin - Europe's biggest carmaker Volkswagen AG on Friday unveiled a 25.8-billion-euro (38.2-billion-dollar) investment plan in the coming three years.

The move came as the group also said it was acquiring the insolvent German auto parts group Karmann.

The announcement by German-based VW came after group's supervisory board moved to pave the way for its planned takeover of the luxury sportscar maker Porsche.

VW said in a statement that its board had signed off on Thursday the contracts setting out details of the two carmakers' tie-up.

Under the deal, Stuttgart-based Porsche's core sports car operations are to be integrated into VW as its 10th brand.

Announcing its move to takeover Karmann, VW said it plans for form a new subsidiary.

Of the 25.8-billion-euro investment plan, investments in property, plant and equipment will account for 19.9 billion, half of which will be invested in Germany alone, VW said. (dpa)