Portugal has become the first country to meet Europe Union fuel-efficiency goals for cars, and Japan's Toyota is the brand that is closest to meeting the same target across Europe, a report showed on Monday.
The EU, home to 500 million people, has set a target for cutting average emissions from new cars to 130 grams of CO2 per km by 2015.
Manufacturers have driven down average emissions from new vehicles to 140.9 grams in 2010, down from 145.8 grams in 2009, according to a study of 19 EU car markets by auto information group JATO.
Average car emissions in Portugal's new car market were 127.4 grams in 2010, followed by France, Denmark and Italy, which were all below 133 grams.
Sweden has made some of the biggest improvements, but remains one of the most polluting car markets, alongside Germany, with more than 150 grams.
Volvo made the biggest improvements among manufacturers, with a 13.8 percent cut to emissions, while Toyota is the closest to meeting its 2015 target.
Car manufacturers have been given their own individual targets, differentiated according to the size of the cars they produce.
Fiat Group has the most economical cars.
It also has the most ambitious 2015 target of 116.1 grams, and has to make an 8.4 percent cut to get there from its 2010 level of 125.9 grams, the report says.
Toyota has a less stringent target of 124.8 grams, as it makes bigger cars, but with average emissions already down to 130 grams in 2010, it only has to achieve 4.2 percent cuts by 2015.
The report broadly confirms the findings of green transport campaigners T&E, and the European Commission.
(Reporting by Pete Harrison)