The European Union's executive body proposed Wednesday to further limit passenger cars' greenhouse gas emissions by 2020, a move likely to stir unease in an industry already complaining about low profit margins and overcapacity in Europe .

The European Commission, which has executive powers in the EU, proposed to limit CO2 emissions to an average of 95 grams per kilometer by 2020, down from a target of 130 grams already set for 2015. Last year, passenger cars emitted an average of 135.7 grams of CO2 per kilometer.

"We are not only protecting the climate and saving consumers money, we're also boosting innovation and competitiveness in the European automotive industry," said Connie Hedegaard, the E.U. commissioner for Climate Action, in a statement. "More CO2 reductions beyond 2020 need to be prepared," she added.

The proposal seeks to give more long-term certainty about E.U. efforts in fighting climate change to one of the most hydorcarbon-dependent sectors of its economy--also one of the most influential industries, given its prestige and the number of people it directly or indirectly employs.

The proposal, which would turn an existing goal into a legally binding target, will have to be backed by the European Parliament and by a large majority of E.U. governments.