Even as it plans to rid Kathmandu Valley of vehicles over 20 years old, the government has decided to continue to allow the import of vehicles that run on liquefied petroleum gas (LPG). Environmentalists claim LPG vehicles are not clean as they are made out to be. Martin Chautari estimates there are about 900 LPG-powered vehicles in Kathmandu Valley, 600 of them Tuk-Tuks and the rest microbuses. Because these vehicles run on subsidised cooking gas, the import of LPG shot up from 2,500 metric tons a month a year ago to 3,700 tons now. The use of LPG in the transport segment is also a major reason for the shortage of cooking gas in the Valley.