Bs Reporter / New Delhi September 12, 2008, 0:16 IST Differences of opinion between the chairman and a member of the Petroleum and Natural Gas Regulatory Board (PNGRB) on whether existing city gas companies would be allowed to expand their operations came out in the open today. At an industry conference in New Delhi, Chairman Labanyendu Mansingh said cities such as Noida, Faridabad and Gurgaon, for which Delhi-based Indraprastha Gas Ltd (IGL) has already been given permission for setting up gas networks, would be put up for bidding after Reliance Gas, a subsidiary of Reliance Industries, submits an expression of interest for these cities. However, BS Negi, member (infrastructure), said since the rights for these cities had already been given to IGL,