With 621bhp from its 6-litre W12 engine, will the Continental Supersports be the most powerful Bentley ever produced? It's the fastest, certainly - with a top speed of 204mph. However, as bizarely as it seems, its makers are pushing its green credentials, as the new car runs on biofuel as well as petrol.

To cope with the additional power, the Supersports receives uprated brakes and suspension, and a ‘Quickshift’ automatic gearbox. Engineers on the two year test and development programme have also focused on slimming the GT - and thanks to the additon of lightweight components such as carbon-fibre seats, the car has lost 110kg compared with the GT Speed.

Visually, the Supersports is beefed up with an aggressively styled bodykit, which boasts flared rear arches and wider side sills - although it's more than a cosmetic tweak, as the rear track has been increased. New 20-inch 10-spoke alloys, and smoked brightwork complete the exterior upgrade.

Performance is improved - 0-60mph is despatched in 3.7 seconds, 100mph comes up in 8.9, and mid-range acceleration borders on the interstellar, with a 50-70mph time of 2.1 seconds. However, with E85 bioethanol compatibiity, Bentley is claiming that exclusive use of this fuel reduces CO2 output by 70%. Bentley has also confirmed that the rest of its range will be 'Flex Fuel' cars by 2011.

Prices and production numbers are yet to be confirmed, but expect to be writing a £150,000 cheque to get  one in your garage..