Stuttgart - Ferdinand Piech, the German industrialist at the centre of a titanic struggle over the fate of Porsche, has agreed to an outside investor helping to save the sports-car maker, Porsche said Wednesday.

Piech, who owns 13 per cent of Porsche, has advocated Porsche's absorption into Volkswagen Group, where Piech is board chairman. He had earlier criticized efforts to bring in an Arab investor as co-owner of Porsche.

The entire Porsche and Piech clan were now united behind the bid to attract an investor, said a spokesman at Porsche, which is struggling under a debt burden of 9 billion euros (12 billion dollars).

Despite the announcement, it remained unclear where Porsche and its chief executive Wendelin Wiedeking, who has made the preservation of Porsche's independence his main goal, were headed.

On Tuesday evening Piech and clan patriarch Wolfgang Porsche had issued a brief joint statement that they were pursuing the goal together of an "integrated automobile group," which seemed to some observers to be a contradiction to seeking help from an Arab fund.

Analysts said this seemed to be a warning from the family owners to Wiedeking to yield to Volkswagen's demands for all the facts.

Last year, Porsche mounted an ill-fated attempt to take over larger Volkswagen, and Piech has made no secret in the past week of his animosity towards Wiedeking, 56.

The German state of Lower Saxony said this week it was contemplating a solution where it retains 20 per cent of the merged group, the Porsche and Piech clan hold about 50 per cent and an Arab fund obtains 30 per cent. (dpa)