Italian automaker Fiat has topped a list of Europe's best performing car companies in terms of carbon dioxide (CO2) output.

The list, compiled by automotive analyst JATO Dynamics, found that the average CO2 output of Fiat vehicles during the first six months of 2010 was 123.5 g/km, an improvement of 4.3 g/km on its 2009 result.

Toyota came next with an average output of 128 g/km, helped by the continuing success of the Prius, the five seater with the lowest overall carbon dioxide in Europe.

French brands Peugeot, Citroen and Renault were in third, fourth and fifth place respectively.

The cleanest car overall was the Fiat 500, emitting 116 g/km, followed closely by the Fiat Panda with 118.9 g/km and the Ford Fiesta with 122.7 g/km.

All twenty of the top-selling cars in Europe reduced their CO2 output in the first half of 2010, the statistics showed, although the Audi A3 and Opel/Vauxhall Corsa were the most improved thanks to powertrain enhancements.

In total, JATO Dynamics said that it had seen a significant reduction in the carbon dioxide output of vehicles, which it said was "triggered by a perfect combination of manufacturer effort, macro-economic conditions driving demand for greater efficiencies and taxation schemes  to shift buyer behaviour."

Almost 60 percent of European vehicles are now at or below the 140 g/km carbon dioxide level - the European Union has mandated that 65 percent of new cars must emit a target of 130 g/km in 2012, rising to 75 percent in 2013, 80 percent in 2014 and 100 by 2015.

Europe's cleanest cars

1. Fiat 500
2. Fiat Panda
3. Ford Fiesta
4. Fiat Punto
5. Citroen C3
6. Volkswagen Polo
7. Opel/Vauxhall Corse
8. Peugeot 207
9. Renault Clio
10. Audi A3/S3

Volume-weighted average CO2 emissions, figures compiled by JATO Dynamics.

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