In a move that could give a fillip to India's unconventional gas production, the ministry of environment and forests has given the phase-III clearance for Essar Oil's Raniganj block in West Bengal. The company will now be able to drill up to 650 wells, compared with the current 135.

The clearances would help Essar Oil invest another Rs 2,500 crore to increase the number of drilled wells to 300 by the end of this year and also rise production to three million standard cubic metres of gas per day (scmd), up from around 60,000 scmd.