A squeeze in supply of cheap local natural gas in the future can erode the margins of city gas distributors but the business would remain viable due to the present price advantage gas has over petrol and diesel at present, state’s support for the cleaner fossil fuel and creation of an efficient gas ecosystem over time in the country, said the chief of downstream regulator. The Petroleum and Natural Gas Regulatory Board (PNGRB), the downstream regulator, has worked overtime in a year to give away city gas distribution licences for 136 geographical areas, aimed at raising piped gas coverage to 70% of the country’s population from 20% now.