Chris Davies, a legislator who is leading the proposals through the European Parliament, said manufacturers might have to use 20 percent of their advertising space to detail cars' environmental impact, just as cigarette packs carry health warnings today.

"We're talking about the future of the planet, so I think its not unreasonable to have certain requirements," he told reporters ahead of the proposals being debated next Monday and voted on next Wednesday.

Car makers face mandatory cuts after making slow progress to meet voluntary targets over the last 12 years.

The proposals have led to frantic lobbying and sparked tension between makers of lighter cars with lower emissions, mostly based in southern Europe, and makers of more powerful cars with higher emissions from northern Europe.

"What will go through on Wednesday is a cut to 125 grams by 2015," said Davies. "I know we have a majority for that ... even the Germans who are lobbying hardest against this legislation, can live with that. Give them seven years and they've got no excuse."

But while the timeframe has been eased, car makers will not be allowed to meet the targets through other CO2 saving measures, such as biofuels, special tyres, air-conditioning improvements and indicators telling the driver when to change gear.

"We want them to do it by technical means alone," said Davies. "Let's make it wriggle-proof.

"The trouble with complementary measures is that it depends on the driver," he added, referring to gear shift indicators. "If you happen to have an 18-year old who likes to have his engine roaring, you can't account for that."

The proposal would not set legislation but sets down a consensus of European Parliamentary opinion ahead of laws that could be enforced by mid 2009.