US-based 
companies Hunt Oil and Noble Energy have serious interest in taking part 
intenders for oil and gas exploration in two blocks in the Black Sea, 
Bulgaria's ruling party GERB party said on Thursday.
Earlier this week, 
GERB quoted senior officials of another two U.S. oil and gas companies - 
Anadarko and ExxonMobil - as telling Bulgarian government officials in Houston, 
Texas, they too are considering bidding in the two tenders. A Bulgarian 
government delegation is in the U.S. for a series of meetings with prospective 
U.S. investors in the two offshore blocks.
In late April Bulgaria's 
energy ministry opened tenders for five-year exploration permits, with an option 
for two two-year extensions, for blocks 1-14 Silistar and 1-22 Teres in the 
continental shelf and the country's exclusive economic zone in the Black Sea. 
The Silistar block covers an area of 6,893 sq km while the Teres block has an 
area of 4,032 sq km.
Hunt Oil has drilling projects in Bulgaria's 
northern neighbour Romania with a team of experts who are familiar with the 
specifics of the Black Sea basin, and will most probably submit an offer for the 
Teres and Silistar blocks, GERB said in a press release, quoting a senior 
company official.
Noble Energy, which has operations in the 
Mediterranean, too is interested in expanding its business to the Black Sea, the 
company's regional manager Tiffany Hopkins said, as quoted by GERB.
On 
Wednesday GERB quoted Anadarko's general manager of international negotiations, 
Eric Fry, as saying the company plans to participate in the two 
tenders.
U.S. oil and gas giant ExxonMobil, too, is examining the 
possibility of taking part, the company's exploration manager Stacey Weltmer 
told the Bulgarian officials a day earlier, as quoted by GERB.
The 
deadline for submission of bids in the two tenders expires on September 
21.
The Bulgarian government has said it expects that the tenders will 
attract the interest of industry majors considering thatFrance's Total, 
Austria's OMV and Spain's Repsol are already exploring the nearby Han Asparuh 
block in the Black Sea.
Romanian media have reported that OMV Petromand 
ExxonMobil have discovered a significantgas deposit in the nearby Neptun Block, 
in Romanian territorial waters. The value of this discovery is estimated at 
around 3.5 billion euro ($3.97 billion), according to business daily Ziarul 
Financiar.