LONDON — Sebastien Buemi has won a Formula One seat with Toro Rosso and is expected to be the youngest driver on the F1 circuit in 2009.

The 20-year-old Swiss competed in the GP2 series last year.

"Our engineers have been impressed with his speed in the car and his ability to learn and progress during the testing he has carried out for us last year," team chief Franz Tost said Friday. "That, along with some impressive performances in GP2 was enough to convince us to give him the drive."

Buemi was also a reserve driver last year for Toro Rosso's sister team, Red Bull Racing. He came up through Red Bull's junior driver program.

"Being a Formula One driver has always been my target, since I first started racing," Buemi said. "This year, I will do all I can to bring home the best possible results and to show Red Bull that the confidence it has shown in me is justified."

Buemi's first official track outing will be at the test session at the Portimao Circuit in Portugal later this month.

Toro Rosso must still decide on its other driver for 2009, including whether to retain Frenchman Sebastien Bourdais.