“New Delhi, battling severe pollution over the years, has taken a major policy leap to improve its air quality. Beginning April 01, the Indian capital city’s fuel stations have been selling only Bharat Stage VI (BS-VI) fuel, the cleanest category available in the country today.” 
Quartz
Read it on Delhiair.org:
One of the world’s most polluted capitals now sells only the cleanest fuel available
delhiair.org - be informed and active about air quality in New Delhi, India 