"If car manufacturers make no further improvements in carbon efficiency of new cars between 2010 and 2012, non-compliant manufacturers could face fines which in total would add up to 10 billion euros," the EAA said.
Large auto manufacturers face being fined if they fail to meet a directive for lowering emissions of carbon dioxide (CO2), the principal greenhouse gas.
The emissions target across the industry is an average of 130 grammes of CO2 per kilometre per new passenger vehicle. Within this collective target, companies have individual goals based on the average of their fleet.
From 2012, 65 per cent of a company's newly-registered cars in the European Union must meet the target. In 2013, the threshold will rise to 75 per cent, to 80 per cent in 2014 and finally 100 per cent in 2015.
As of 2010, 32 manufacturers representing almost 80 per cent of new registrations achieved the 2012 objective, the Copenhagen-based agency said in a report.
Those in front are Japan's Toyota, followed by the French companies Renault and Peugeot-Citroen, which also are between just one and five grammes short of their 2015 targets.
Laggards are Daimler, Skoda, General Motors-Daewoo, Nissan, Mazda and Dacia.
"Today, people use many forms of transport but cars still represent a big part of everyday life," EAA Executive Director Jacqueline McGlade said.
"The data show that most car manufacturers have already met their individual 2012 targets. However, several others need to continue their current trend of year-on-year efficiency improvements."
The directive offers flexibility to manufacturers who introduce cars with very low -- less than 50 grammes of CO2 per kilometre -- emissions, who make vehicles that run on E85 biofuels or who use experimental CO2-reducing technology.
Road transport accounts for 17.5 per cent of Europe's overall greenhouse gas emissions which increased by 23 per cent between 1990 and 2009, the EAA said.
In 2010, the average emission level of a new car registered in the 27 EU nations was 140.3 grammes of CO2 per kilometre, compared with the EU 2020 target of 95 grammes.
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