Last updated on .From the section Formula 1

Nasr drove for Williams in first practice during last weekend's US Grand Prix

Sauber have announced that Brazil's Felipe Nasr will drive for them in 2015, joining fellow new recruit Marcus Ericsson.

The signings mean that current drivers Adrian Sutil and Esteban Gutierrez will leave Sauber at the end of the season.

Nasr, 22, has been a test and reserve driver for Williams this year while also participating in the GP2 series.

"This is an unforgettable moment that I owe to all of those who have supported me," said Nasr.