From GMM

Nico Hülkenberg's future on the formula one grid is not assured, Sir Frank Williams has revealed.

21-year-old German Hülkenberg is one of the most promising up and coming young single seater drivers, having won the 2006/7 A1GP series, and last year's F3 Euroseries championship.

Complementing his season in GP2, he is now Williams' test driver, and is openly hoping to graduate to motor sport's premier category in 2010.

Germany's Auto Bild asked Williams, the Grove team's boss and co-owner, if Hülkenberg can expect to make his debut next year.

"Obviously I can't directly answer that question," he said.

Tellingly, Williams then referred to the team's existing German race driver Nico Rosberg, whose contract expires this year.

He said: "A lot depends on what happens with our other Nico. But Nico Hülkenberg is on our list, absolutely."