However, these fears have been softened as Russia, the world's second largest oil exporter, could help cushion oil markets against volatile supplies from OPEC nations and political turbulence in the Middle East.

"We see Russia playing a great role in terms of global energy security. By assisting Russia in exploring their energy resources we improve global energy supplies and enhance our trade alliances as well," Abraham told reporters after meeting Russian Energy Minister Igor Yusufov and local oil firms.

He said the United States would fund a study of offshore oil and gas fields in Russia's eastern Siberia region to determine which offered most potential for development.

"The eastern Siberian offshore oil and gas regions offer some of the least studied and potentially most significant geological basins in the world," he said. The analysis is part of U.S. current geological survey, "Arctic Resource Assessment."

Russian producers are looking to explore untapped oil and gas fields in eastern Siberia, which experts say may yield as much oil as the rich fields of western Siberia.

Russian companies, however, have never mentioned the eastern Siberian Arctic shelf as having potential for huge oil resources. So far only Russia's fifth largest oil producer, Sibneft, is conducting modest exploration in Chukotka, Russia's easternmost region, opposite Alaska.

"I think there was some confusion and the idea is to boost our cooperation in eastern Siberia, the Barents and Kara Sea and the Sakhalin island shelf. But the idea of cooperation is very positive," a Russian participant in talks with Abraham said.

MORE PROJECTS IN HOUSTON

U.S. oil giants have been so far modestly active in Russia, unlike European majors, who have been rushing over the last year to acquire new reserves in the country, taking advantage of Russia's improving political and economic climate.

"President (George W.) Bush's national energy policy calls for increased international cooperation to improve our energy security through the development of energy resources throughout the world," Abraham said.

"We recognise that one of the main challenges Russian energy sector is facing is access to markets".

"One of the goals of the summit in Houston is to bring Russian and U.S. companies together to better familiarise them with challenges and opportunities in Russia," he added. Russia currently exports up to three million barrels per day of crude to world markets. Its oil output is booming for the fourth consecutive year and the country needs to build new export routes as its domestic consumption is barely increasing.

Russian oil firms, which typically ship their crude to Europe, have said they are ready to supply more crude to the United States but need more deep water ports and new logistics to bypass the crowded Turkish straights on the Black Sea and the Danish straight in the north.

Russia's second oil producer YUKOS has already made the country's first ever large crude direct shipment to the United States in June, selling two million barrels of oil to ExxonMobil.

A second tanker sailed in July and another is due to leave next month, with plans to send up to six to the U.S. Gulf Coast by the end of the year.

Abraham has also been holding talks with Russia's atomic energy officials and raised yesterday strong objections to Russia's cooperation in nuclear power with Iran, including plans announced last week to build up to six reactors in the country.