The overseas-arm of the state run ONGC [Get Quote], ONGC Videsh, which paid $1 million for acquiring data in the Mannar offshore basin in Sri Lanka, and Cairn India [Get Quote] have bid for oil exploration blocks in the Island country.

"While the ONGC Videsh (India) Ltd has bid for block No 1, the Cairn India has submitted bids for block 2 and 4," the Sri Lankan Petroleum and Petroleum Resources Development Minister A H M Fowzie told PTI.

Studies reveal a potential for one billion barrels of crude oil in the Mannar offshore basin, he said, adding "we will get the first barrel of crude oil by 2010." Niko Resources (Cyprus) Ltd has bid for block no 3, the minister said, adding that the evaluation of all bids will be finalised in three months.

The international arm of the ONGC has already bought the Norwegian group TGC NOPE's seismic survey for one million dollars for acquiring data on the Mannar Offshore Basin. Fowzie said the work on the blocks for tapping oil would commence from August.

As many as 18 oil and 11 gas reserves have been identified on the Indian side of Cauvery Bay. The Mannar Basin, located between southwestern Sri Lanka and Indian coastline in water depths ranging from 50 m to over 3,000 m, is estimated to be rich in both oil and gas.

Besides the bids on offer, Sri Lanka has offered one block each to India and China on a nomination basis. The country offered to give OVL 5,000-6,000 sqkm of exploration area in the Mannar Offshore Basin on nomination basis. This is in lieu of assistance in training their professionals and marking the exploration and production blocks.