NEW DELHI: The Delhi government has urged Haryana to allow only BS VI-compliant buses to enter the national capital from October 1 in order to help control air pollution in the city. The request was made to deal with the problem of vehicular pollution in the city, which officials indicated is contributed to in part by vehicles coming from the neighbouring state of Haryana. The national capital witnessed high levels of air pollution in the winter months of October due to a multitude of factors, including stubble burning and vehicular traffic. In a June 15 letter to Haryana Transport Department Principal Secretary Navdeep Singh Virk, Delhi’s Transport Special Commissioner OP Mishra has said the situation has attracted the attention of the Supreme Court and the CAQM (Commission of Air Quality Management in Delhi and NCR). They have issued directions for effective regulation of air pollution and vehicular pollution, he said.In its order on October 14, 2018, the Supreme Court had directed no motor vehicle conforming to the lower BS-IV emission standard shall be sold or registered in the entire country from April 1, 2020, and only BS-VI compliant vehicles are permitted to be sold or registered, the letter said. The letter said the National Green Tribunal has already directed that diesel vehicles more than 10 years old will not be allowed to ply in the NCR.