Three energy giants have submitted bids for exploration and exploitation of natural gas in the so-called "Khan Asparuh" block in Bulgarian Black Sea waters.

According to Bulgaria's Economy and Energy Minister, Delyan Dobrev, the three are the US Exxon Mobil, the French Total, and the Canadian Melrose.

Dobrev spoke Thursday at the conference "Exploration and Production of Oil and Gas –the New Technology Frontier."

The successful bidder will be announced by the end of July, he explained, adding that in addition to natural gas, there was some potential, though not as big, of finding oil.

"Our hopes to discover significant quantities of natural gas are huge. They stem on one side from such energy giants bidding for the tender, but on the other, on the fact that a deposit was discovered just 15 km from our northern border with Romania. Such deposit can very well satisfy demand of gas in Bulgaria for 10-20 years," the Minister stressed, adding he was not talking about a possible joint deposit in the Black Sea with Romania.

In addition to the July deadline to announce the winning bid, others listed by Dobrev are: September to sign the concession contract; the end of the year to start analyzing geological data, and end of 2013 to make the first drill, depending on the bidders' company plans. All exploration works must end in 5 years.

"I am extremely optimistic about the Black Sea because our block is much larger than the Romanian one," he concluded all while explaining that there are no territorial issues whatsoever between the two countries.

In addition to the Black Sea, Bulgaria hopes to discover about 3 B cubic meters of gas (about 30% of the total needs of the country) near the village of Deventsi where the US Direct Petroleum Transatlantic is doing the exploration works.