The European Commission has published proposals aimed at reducing vehicles' carbon dioxide (CO2) emissions by 2030.
The move is designed to put further pressure on manufacturers to develop more hybrid and electric cars.
The Commission also wants to introduce an incentive scheme to encourage companies to produce more zero and low-emission cars.
Under its plan cars and vans will have to emit 15% less CO2 by 2025 compared with 2021 and 30% less by 2030.
"The proposed 30% reduction target for passenger cars is ambitious and realistic," the Commission said.
Any changes would not apply to the UK if it was no longer in the European Union.
The Commission acknowledged that the technical changes needed to achieve the new targets would mean higher production costs and that would, in the short term, lead to higher vehicle prices.
It calculated that for an average new car registered in 2030, the additional manufacturing costs would be about €1,000 (£883). For an average 2030 van, they would be up to about €900.
"However, these additional costs are significantly lower than the fuel savings from which consumers will benefit over a vehicle's lifetime," the Commission said.
Read more at: bbc.com