The Smart fortwo cdi, apart from being fun and stylish, now tops the environmental friendliness rankings, Mercedes-Benz says.

This diesel model first made the motoring world take notice with its carbon dioxide emissions of just 88 grams per kilometre, the lowest figure in the world for cars with a combustion engine.

Now the smart fortwo has set a new record with emissions of just 86g/km, or consumption of 3.3l/100km with its transmission's manual "softip" mode engaged.

To achieve these figures, Smart improved the vehicle's aerodynamics. One of the changes was to reducing ride height by seven millimetres.

Smart brand managing director Marc Langenbrinck says: "We continue to work hard to make our smart models even more environmentally friendly. The smart fortwo cdi - the past and the present CO2 champion - is proof of this. And the next level of sustainable drives is ready to go: the smart fortwo electric drive has already been proving itself in everyday use in London for three years. Series production of 1000 vehicles started in November 2009.

"From 2012 the dream of motoring with no local emissions will become a reality for everyone. Lots of people are talking about electric drive - but we already have it on the road.

"This confirms smart's role as a trendsetter - ten years ago as the first true city car and now among electric vehicles. With its fleet smart has an excellent position with regard to corporate average CO2 emissions."