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(Adds details on aim of planned sanctions, changes dateline toWASHINGTON)
By Timothy Gardner
WASHINGTON, Sept 10 (Reuters) - The United States andEuropean Union plan to stop billions of dollars in oilexploration in Russia by the world's largest energy companiesincluding Exxon Mobil Corp and BP Plc, U.S.government sources said.
The planned sanctions over Russia's aggression towardUkraine would ban U.S. and European companies from cooperatingwith Russia on searching its Arctic territory, deep seas orshale formations for crude, said two U.S. officials who spoke oncondition of anonymity because the measures have not been madepublic.
The measures, which one of the sources said represented"preliminary thinking," would expand sanctions the Obamaadministration announced in July and ban U.S. and EU cooperationon all energy services and technology in the unconventional oilfields. The previous sanctions only banned some technology atthose locations.
Russia, along with the United States and Saudi Arabia, isone of the world's top oil producers and is the main energysupplier to Europe. But its conventional oil fields are indecline, so it must move to frontier sources in Siberia and theArctic to keep the oil flowing.
Exxon signed a $3.2 billion agreement in 2011 with Russiancompany Rosneft Oil Co to develop the Arctic. TheTexas-based multinational was considered one of the fewcompanies capable of drilling in the harsh, deep waters there.
The new sanctions, if applied, would be harmful to Russia'sfuture prospects because they would target fields five or 10years from producing oil. But application of the sanctions couldbe prevented if Russia sticks to a cease fire, and depends onseveral factors including actions by the EU.
The planned sanctions were first reported by Bloomberg.
European Union officials have delayed a decision on whetherto implement measures against Russia. They will meet for furthertalks on Thursday.
Once the EU implements the new ban on sharing energytechnology and services, the United States would follow suitwith similar measures, including barring the export of U.S. gearand expertise for the specialized exploration that Russians areunequipped to pursue on their own.
Last week, a U.S. envoy in Brussels told Reuters thatWashington is considering limiting high-tech exports to Russia'sArctic energy industry as part of plans to strengthen sanctions.
THE GLOVES COME OFF
Any new sanctions on services and technology related toRussia's oil frontier would signal that the United States and EUare "taking the gloves off and are aiming directly at the majorsource of Russia's potential future energy production growth,"said Robert McNally, a White House energy adviser to formerPresident George W. Bush who now heads the Rapidan Group, anenergy consultancy.
He cautioned that the new plan would only succeed if EU andU.S. cooperation is tight. "Both must ensure other countries donot step in and provide services and technology they will bewithdrawing," McNally said.
In July, Exxon began bringing a rig called West Alpha fromNorway to the Russian Arctic. The company is hoping for a majordiscovery in the Kara Sea with Rosneft.
Exxon spokesman Alan Jeffers declined to comment on thefuture of the rig but said it is company policy to comply withall laws and that it is assessing sanctions on Russia.
BP will study the sanctions and "as always we will complywith all applicable sanctions," said spokesman Brett Clanton. (Reporting by Timothy Gardner and Josephine Mason in New York;Editing by Ros Krasny, Tom Brown and Cynthia Osterman)
