India’s Supreme Court Allows New Delhi’s Diesel Ban

India’s Supreme Court has allowed New Delhi to continue its ban on the sale of new vehicles powered by diesels displacing more than 2.0 liters.

The city, described by the World Health Organization as the world’s most polluted, announced the ban last month in an effort to improve air quality. The restriction will continue through April. In recent weeks the concentration of harmful PM2.5 micro-particles in the city’s air has been as much as 23 times the maximum considered safe by WHO.

Multiple carmakers challenged the ban, arguing that new diesels are dramatically cleaner than the previous-generation engines that dominate the city’s diesel population. Mercedes-Benz is being hit hardest, because 70% of its sales in India are diesel-powered cars—all of which have engines larger than New Delhi’s cap, according to Bloomberg News.

The city’s diesel restrictions come as India prepares tighter emission standards for all diesels, including those powering India’s unique mini commercial vehicle market. The planned new rules would slash allowable emissions 95% by 2019, notes the Mumbai-based Economic Times.

ET says technologies to achieve the cuts are not well-suited to the low-power diesels used in mini-trucks. Manufacturers tell the newspaper that meeting the new standard could hike diesel engine costs more than 20%.