George Clooney is auctioning his 2008 Tesla Signature 100 Roadster to raise funds for relief work in Sudan.

The Descendants star has clocked up just 1,700 miles on the car, and it is expected to fetch up to $125,000.

The car, one of the original models of the two-seater sports car, will be auctioned off by Gooding & Company at the Pebble Beach Concours d'Elegance in Los Angeles on August 19.

President and founder of the auction company, David Gooding, said: ''We are overjoyed to present George Clooney's Signature 100 Tesla at Pebble Beach because this is an incredible opportunity to purchase a modern collector car with all the right elements; one-owner, celebrity provenance; historical significance; limited-edition rarity and philanthropic ties.''

Proceeds from the sale will be donated to the Satellite Sentinel Project, which was co-founded by George and activist John Prendergast.

The charity uses satellite pictures to monitor the Sudanese region for evidence of ''alleged atrocities''.