The owners of indebted automotive group Porsche SE have agreed in principle to accept Volkswagen's plan for a merger but the deal awaits final approval, German newspapers reported yesterday.

The idea is for Volkswagen to acquire just under half of the Porsche group's healthy Porsche AG sports car business, a concept pushed for months by VW chairman Ferdinand Piech, the Financial Times Deutschland and Die Welt reported.

Europe's biggest carmaker would eventually take over all of Porsche AG, adding a 10th brand to its line-up, according to the reports.

A Porsche spokesman said he was unaware of any such agreement by members of the Porsche and Mr Piech families, who control all the voting rights in Porsche SE.

VW had no official comment.

The end game in thorny merger talks between Porsche and Volkswagen looms on July 23 when the carmakers' supervisory boards meet separately in Porsche's home town of Stuttgart. The Porsche and Mr Piech families have been at loggerheads for months over how to resolve Porsche's debt woes and the role VW would play in the whole deal.

Porsche had to abandon plans to take full control of its much larger peer as its debt mounted just as global car markets collapsed. That left Porsche with a 51 per cent stake in VW.