Heaton said Cairn had already found gas at Semutang field in block 15 during an exploratory drilling in 1997. He said: "We have tested gas in Semutang but the reserves are not yet known.

Cairn has already found nearly 850 billion cubic feet of gas reserves at Sangu offshore field in block 16, the first by any company to strike a reserve in the Bay of Bengal. The company started supplying 60 million cubic feet of gas per day from the field in the middle of this year.

But Heaton said that Sangu could produce more than 160 million cubic feet of gas as was stipulated in the contract. CairnEnergy in a joint venture with Royal Dutch Shell participated in the second lisencing round for six blocks but was only offered block-5 in a partial result announced on July 26, more than a year after the country called the bidding.

Bangladesh has made known the results of only five blocks out of 15 it offered for bidding. Heaton said his company was disappointed by the delay which cost the participating companies their "valuable time."

"We are waiting to see what happens regarding the final outcome of the lisencing," he said, adding that Bangladesh should have coherence in its energy policy to attract foreign investment.

Bangladesh has proven gas reserves of about 10.5 trillion cubic feet, but experts say it could rise to 50 trillion cubic feet based on the pace of success to date. "Every third well on an average there has been discovery of gas. We think it is a good rate of success," Heaton said.