BMW led the industry in reducing year-over-year carbon dioxide emissions from its fleet, according to a new report.

New BMWs sold in the European Union last year emitted 7.3 percent less CO2 compared to 2006 models, more than four times the industry average, a report from the European Federation for Transport & Environment (T&E) found. Overall emissions rates for carmakers improved by just 1.7 percent.

"With the threat of legislation looming, BMW has shown that even premium carmakers can seriously reduce CO2," said T&E's Jos DIngs in a statement. "But the slow response of most carmakers shows that the EU needs to keep up the pressure with challenging, long-term CO2 targets."

On average, carmakers must slash emissions form fleets 17 percent to satisfy a proposed EU 2012 target of 130 grams of CO2 per kilometer. BMW's new cars in 2007 averaged 170 g/km. The average new car sold in the EU last year produced about 158 g/km.

While German automakers as a whole showed the greatest year-over-year improvement in cutting emissions, French manufacturers had the lowest average emissions rate of 143 g/km, while new Japanese cars carried an average of 157 g/km.

The report said the results, based on 2007 car sales in 18 EU member states, can be attributed to lack of progress in cutting vehicle weight. It called for a long-term target of 80 g/km by 2020.

The EU wants to shave emissions by more than 20 percent from 1990 levels by 2020. It will vote on the vehicle emissions law early next month.