By GMM

Other European car manufacturers are considering joining the action on the formula one grid, according to BMW-Sauber boss Mario Theissen.

The German said he understands Audi, Volkswagen and Porsche are interested in the sport's current direction; like BMW's trajectory of success with a reasonable budget, and road-relevant new technologies like KERS.

Theissen also said some Asian manufacturers could follow suit.

"If the introduction of KERS is successful next year, as I expect it to be, it will be the best case I have seen in 10 years in formula one of a synergy with road cars," he told The Times.

"Already my colleagues in the road car research and development department are knocking on our door," Theissen added.