Sri Lanka has eight oil and gas exploration blocks in the northwestern Mannar basin, two of which have been granted to the governments of China and India.

"We will drill three wells. In four months after drilling, we will be able to say if there is oil and gas in the basin and it will take another two years to assess how much oil and gas are there, if any. Altogether, if there is oil, it will take a minimum of six years to start commercial production," Stuart Burley, the head of geoscience at Cairn India, told Reuters.

A Petroleum Resources Agreement was singed in 2008 between Cairn India and the government to explore and produce hydro - carbon and natural gas in the Mannar Basin in Northern Sri Lanka.