Sales of diesel cars will continue to plunge, according to a study by Aston University.
It predicts they will account for just 15% of the UK market by 2025, after peaking at 50% in late 2016.
Automotive expert Professor David Bailey told the BBC diesel’s “slow death” was being driven by “environmental pressures and consumer confusion”.
He is urging the government to set up a scrappage scheme to encourage drivers to switch to electric cars.
“The time is right for the government to take the initiative and offer up scrappage benefits to those who are prepared to ditch their diesels and switch to electric cars,” he said.
Figures released by the Society of Motor Manufacturers and Traders (SMMT) last week showed sales of new diesel cars fell by 17.1% last year.
The market share for petrol cars increased from 49% in 2016 to 53.3%, and alternatively fuelled vehicles were up from 3.3% to 4.7%, while diesel declined from 47.7% to 42%.
Aston University expects a further 10% drop in sales this year and says diesel will account for less than a third of the market by 2020.