While putting off extension of diesel vehicle ban to other cities in the country, the National Green Tribunal, on Tuesday, asked all states to identify two most polluted cities in their states within three weeks. Additionally, it has asked states to file a detailed affidavit on vehicular pollution in these two cities, the different sources of pollution, data on petrol and diesel emissions, ambient air quality and impact of mining and industries on air quality. “We need complete data and through their secretaries, the states should file affidavits within three weeks,” said Swatanter Kumar, chairperson, NGT.<!– /11440465/Dna_Article_Middle_300x250_BTF –>Earlier on Monday, the NGT bench had asked all states to submit data on cities worst affected by pollution. But most states asked the bench for more time to submit the data. Only Uttar Pradesh, Punjab, Jharkhand and Bihar was ready with data on pollution.After the Supreme Court banned registration of new diesel vehicles and the southern bench of NGT banned diesel vehicles in Kerala, a petition was moved to extend the ban across other major cities. Meanwhile, the union ministry of heavy industries had opposed the plea for extending the ban to other cities. Arguing against the plea for the ministry of heavy industries, additional solicitor general Pinky Anand, said, “A lot of investment is coming in the sector which will provide a lot of employment opportunity. A ban will also affect Make In India.”Society of Indian Automobile Manufacturers, too, opposed the extension of the ban. Appearing for SIAM, senior lawyer Abhishek Manu Singhvi argued that instead of using a “sledgehammer” approach, any decision should be taken after source apportionment studies are carried out. “We need source apportionment studies that provide data on emissions fuel wise and also as per vehicles,” said Singhvi.