According to Centre for Science and Environment, the move to BS-VI will bring down Nitrogen Oxide emissions from diesel cars by 68% and 25% from petrol engined cars.

In what can be seen as perhaps India's boldest move to curb air pollution, the government has decided to advance the standard for cleaner cars and leapfrog to Bharat Stage-VI emission norms countrywide by April 2020. That's one year earlier than the deadline announced last month.Currently, Bharat Stage-IV fuel is supplied in whole of north India. The rest of the country gets BS-III grade fuel. The government has decided to altogether skip Bharat Stage-V."Most car manufacturers in India are making Euro 6 compliant engines in India and exporting them. They have the technology available and time till 2020," said transport minister Nitin Gadkari. Bharat Stage-VI is equivalent to Euro 6 emission norms.The Oil Ministry has assured the supply of Bharat Stage-VI fuel to meet this promise. For this, two-thirds of India's state-owned refineries will need upgradation and the government says it will cost them Rs 60,000 crores.According to the Centre for Science and Environment, the move to Bharat Stage-VI will bring down Nitrogen Oxide emissions from diesel cars by 68 per cent and 25 per cent from petrol engined cars. Cancer causing particulate matter emissions from diesel engined cars will also come down by a phenomenal 80 per cent."This is a game-changer. This move was much needed since India is 10 years behind Europe. It will not only help reduce public health impact of motorisation but will also positively impact the climate problem," said Centre for Science and Environment's Anumita Roy Chowdhury.2020 is also the year when the Paris climate agreement, which India signed in December last year, will come into effect and the first five-yearly compliance report will be filed.Reactions from car companies have been mixed."Society desires that we move to Bharat Stage-VI. As a company we'll do everything possible to meet these new norms. The only issue is I want government's announcement to be firm, not changed," Vikram Kirloskar, Vice Chairman, Toyota Kirloskar Motor told NDTV.Mercedes Benz told NDTV, "We welcome the government's move. We should look at introducing this even earlier as we have the Euro 6 vehicles readily available with us."With air pollution levels at an alarming high in Delhi, the Aam Aadmi Party has demanded Bharat Stage-VI by 2017. While the Centre could ignore the Delhi government's demand, it still has to explain to the Supreme Court after it asked the government on Tuesday why Bharat Stage-VI can't be brought in by 2019.