Diesel engines are being phased out over time as hybrid and electric cars become more common.

In order to encourage greener transportation, a government group has suggested banning diesel vehicles

by 2027 in cities with a population of over a million people. By the end of this decade, 

no diesel city buses should be operating in metropolitan areas, according to the research. 

The administration has not yet accepted this report, though. 

The panel's suggestions, according to the government, are futuristic. 

 A final decision on whether to enact such prohibitions must be made after extensive discussion

Currently, diesel-powered vehicles contribute to about 40 per cent of sales in India