Russian President Dmitry Medvedev visited Turkmenistan on Friday in a bid to consolidate Moscow's monopoly on energy transit from Central Asia.
Russia has sought to undercut the Western push for the region's rich energy resources by buying most of its natural gas for exports to Europe.
Medvedev is expected to push Turkmen President Gurbanguli Berdymukhamedov to continue shipping the bulk of its gas to Russia.
Russia controls westward export pipelines for gas from Turkmenistan, which has the largest reserves in the former Soviet Union after Russia and produced around 2.6 trillion cubic feet (73 billion cubic meters) last year.
The Kremlin reached a deal with Kazakhstan and Turkmenistan in December to build a new natural gas pipeline along the Caspian Sea coast to Russia. The agreement dealt a blow to the European Union's hopes to ease its increasing energy reliance on Russia, which supplies a quarter of Europe's gas and is its second-biggest supplier of oil.
The U.S. and EU have pushed for construction of a trans-Caspian pipeline that would carry Turkmen natural gas to Azerbaijan, Turkey and then to Western markets, bypassing Russia.
Energy-hungry China also has sought a cut in Turkmenistan's gas wealth, reaching a deal to build a natural gas pipeline that is to come on line in 2009 and is expected to reach an annual capacity of 1 trillion cubic feet (30 billion cubic meters).
The growing rivalry for the energy riches of the Caspian and Central Asia region, which is believed to contain the world's third-largest energy reserves, has been widely compared to the 19th century Great Game for dominance in the region between the British Empire and Czarist Russia.
Turkmenistan's policy in the game has been to promise its riches to all players without giving firm commitments.
While Russia boasted a big win in December, its deal with Turkmenistan hasn't been followed by specific agreements and negotiations have continued.
The EU also claimed victory in the spring when Berdymukhamedov pledged to set aside 350 billion cubic feet (10 billion cubic meters) of gas for delivery to Europe from 2009. But analysts were skeptical, pointing that Europe now can't gain access to Central Asia's gas resources without Russia's involvement.
Russia sought to circumvent the EU's push for Turkmen gas by offering to buy as much gas as it can sell at European prices. Medvedev foreign policy aide Sergei Prikhodko said the offer should effectively secure Russia's grip on Turkmen gas.
"After the gradual transition to world prices the issue of the reorientation of these flows to other countries will be removed from the agenda," Prikhodko said, according to Russian news reports.
On his way to Turkmenistan, Medvedev stopped Thursday in Azerbaijan, where he focused on prospective purchases of Azerbaijani gas. He is expected to continue his energy diplomacy tour in Kazakhstan on Saturday before flying to attend the Group of Eight industrialized nations' summit in Hokkaido, Japan.