Heidfeld and Kubica have been rewarded for a solid season

German Heidfeld, 30, will enter his third campaign with the team while Polish driver Kubica, 22, has been rewarded with a second full season.

Both drivers have benefited from BMW Sauber's competitive improvements in 2007 with Heidfeld taking two podiums.

"Nick and Robert have delivered very strong performances," said BMW motorsport director Mario Theissen.

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"Thanks to Nick's extensive experience he is making a substantial contribution to the progress of the team.

"Robert is a rough diamond we want to polish up into a winning driver."

Heidfeld took second place in Canada and third in the Hungarian Grand Prix so far this season and is now looking for further strong results.

"When I look at the progress we have made over the last two years, it's an incredible incentive for me," he said.

Kubica, who survived a 180mph crash in Montreal in his first full season with the team, is the first Polish driver to contest F1.

He said: "I am learning new things every day and making steady progress."