The Government has been urged to take more action to support the UK's liquefied petroleum gas (LPG) industry.
LPG representatives say incentives should be brought in to take the cars with highest emissions off the road, or to convert them into LPG vehicles.
They are also calling for more financial backing for councils planning to acquire a new fleet of environmentally-friendly vehicles.
It is thought that around 150,000 people in the UK are currently driving an LPG vehicle, with a litre of fuel available for around 60p from 1,400 stations across the country.
An increase in the number of LPG vehicles on the road could lead to a significant drop in carbon dioxide, nitrous oxide and particulates emissions, the industry claims.
The announcement comes after the emissions measured in London's Oxford Road breached the overall target for this year in just four days at the beginning of this month.
Autogas Limited general manager Linda Gomersall says the UK needs "a proper integrated fuels strategy" to help tackle air quality and carbon emissions problems.
She said the new framework proposed by the industry contains some "incredibly simple ways" in which ministers could help boost the environment and public health.
Copyright Press Association 2015