New car carbon emissions dropped by 4% in Europe last year the second biggest annual fall on record.
The European Environment Agency said the fall would encourage the car industry to make more green cars.
Last year's improvements bring the average CO2 emissions of cars registered in the EU to 140g/km.
If emissions continue to reduce at the same rate, the European target of 130g/km will be met earlier than the 2015 deadline, the EEA said.
In 2010, 700 pure electric vehicles were registered in Europe. In the UK the figure was 167.