The European Parliament has pushed through legislation forcing car makers to reduce the CO2 output of new cars within four years.
The move is a blow to European car makers, who had expected the EU proposals to be toned down before coming into effect.
In particular, the influential German car lobby had been placing significant pressure on MEPs to 'water down' the controversial proposals. But European lawmakers dismissed their arguments out of hand.
"The German car lobby... has been sent away with its tail between its legs," Liberal Democrat MEP Chris Davies told the BBC.
Politicians on all sides believed a deal had been brokered to look again at the stringent CO2 legislation, as part of an effort to safeguard jobs within the motor industry.
But socialist MEPs - worried about their green credentials - are reported to have voted against the party line, pushing the 130g/km proposals through without revision.
Average CO2 emissions currently stand at 160g/km with manufacturers continuing to explore new technology in an effort to bring this down.