It's a simple and logical solution to improve fuel economy - turn the engine off when it isn't being used. Though this system has been employed by Honda with it's IMA hybrid vehicles, the Paris Motor Show in September will be the first time a Stop and Start system has been available in a solely petrol-engined car when Citroën shows the new C3.

According to Citroën, the average car doesn't need its engine for up to 30 per cent of urban driving - that part of every urban journey when a car is sitting at traffic lights or stuck in traffic jams. The new system allows for the engine to be started automatically the moment the accelerator is touched.

The system has proved in tests to cut fuel consumption by 10 per cent in city driving conditions and emissions of carbon dioxide are also cut by the sameamount.

Though the C3 Stop and Start is ideal for the inner urban conditions of Sydney and Melbourne, Citroën is still considering whether to import the new vehicle.

Citroën Australia's Miles Williams said the company will be examining the car's suitability for Australia very closely. "While we may not have the traffic issues and demands of Paris, or Europe, we do have urban environments where localised pollution is a serious issue and where the Citroën C3 Stop and Start could make a significant contribution to a cleaner environment."