The letter was read out at an oil and gas conference in Baku today.
Kazakhstan's deputy natural resources minister, Ilya Zakimov, said Astana and Baku will sign a deal in the near future. But he did not specify how much Kazakhstan wants to export through the $4 billion pipeline, which carries oil to eastern markets via Georgia and Turkey.
In his letter, Bush also said the United States will continue to work to create a "prosperous, peaceful, and democratic" Azerbaijan.
In a separate letter to Aliyev released by the British Embassy in Baku, British Prime Minister Tony Blair said he hopes Azerbaijan will forge closer ties with the European Union and NATO to build a "secure future" based on "democracy, the rule of law, and an open economy."
Caspian Energy Special
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HOW MUCH OIL? The U.S. Energy Information Administration has estimated that the Caspian could hold between 17 billion and 33 billion barrels of proven oil. ("Proven reserves" are defined by energy experts to be 90 percent probable.) Other experts estimate the Caspian could hold "possible reserves" of up to 233 billion barrels of oil. ("Possible reserves" are considered to be 50 percent probable.) By comparison, Saudi Arabia has 261 billion barrels of oil and the United States 23 billion...(more)