Mention the Caspian Sea to an oil tycoon and his eyes are bound to flare with longing. Ever since the Soviet Union's demise, energy executives have dreamt of tapping the vast petroleum stores beneath the Japan-sized body of water and the post-Soviet nations that surround it -- Kazakhstan, Turkmenistan and Azerbaijan. The US Department of Energy estimates that the Caspian basin contains an eye-popping 110 billion barrels of oil, three times America's proven reserves. The Kashagan field, for example, which has been pumping off Kazakhstan's coast since early 2000, is frequently cited as the biggest oil strike since the discovery of Alaska's Prudhoe Bay in 1969. Some geologists believe that Kazakhstan has the potential to supplant Russia as the world's number two oil exporter, behind Saudi Arabia.

Tapping the Caspian has become a key component of western energy strategies -- particularly for the US, which guzzles over a quarter of the world's oil. Expanding oil production beyond the Middle East is a linchpin of president George Bush's energy plan; he hopes to curtail Opec's pricing power and safeguard against political upheaval on and near the Arabian peninsula. "Through relatively modest, incremental changes in production by the Caspian countries