Bugatti has confirmed that it will build 150 of the new Veyron Grand Sports after the open-top version of the world's fastest car was launched at the Pebble Beach Concours.

Rumours of an open-topped Veyron had been around since the car's introduction, but the Grand Sport was only confirmed for production last year. It will take total Veyron production up to 450 cars by 2011, breaking the company's earlier commitment to build no more than 300 Veyrons.

Like the Veyron 16.4 coupe, the Grand Sport is all about superlatives. Its top speed remains unchanged at 253mph, but the bodywork has been revised to allow high-speed driving with the roof down.