Suzuki will have the cleanest petrol-engined car on sale in the UK when the new Alto, previewed at last month's Paris motor show, goes on sale in spring 2009.
With CO2 emissions of just 103g/km, and average fuel economy of 62.7mpg, it undercuts even the Toyota Prius petrol-electric hybrid, which emits 104g/km.
The only models with lower CO2 in Britain are specially tuned diesel versions of the Ford Fiesta, Volkswagen Polo and Skoda Fabia, which all score just below the 100g/km figure at which cars become exempt from road tax.
The Alto's low CO2 has been achieved without the changes to ride height, engine oil and tyres used by other companies who have introduced ultra-clean cars.
As Suzuki's smallest offering (its just 3.5 metres long), the Alto is naturally lean, with a kerbweight starting at just 855kg. It was designed to have less aerodynamic drag than any rival city runabout; and its 67bhp, 1.0-litre, three-cylinder engine has already proved its efficiency in the company's Splash model.
However, there will be no diesel or special economy versions to allow Suzuki to chase after record low CO2 figures.
Masayuki Fujisaki, manager of product planning, says the company's 1.3-litre diesel doesn't fit the Alto, and that to get a lower CO2 figure from the petrol engine would involve fitting equipment such as engine stop-start systems, which would then increase the price of what is intended to be a low-cost, entry-level model targeted at younger buyers.
Prices in the UK are expected to start at around 7000.