Kazakh state-run energy producer KazMunaiGaz said Thursday that a delegation from the country was in Moscow for talks with Transneft on expanding its stake in the Caspian Pipeline Consortium.

Askar Batalov, executive secretary of the Kazakh Energy Ministry, told reporters that Kazakhstan wanted to boost its interest by about 3 percent from the current 19 percent.

Although the purchase would not bring Kazakhstan's holding to a blocking share, KazMunaiGaz spokesman Arzhan Takachakov said it was "quite natural" for the country to expand its interest in energy infrastructure.

"It is vital in terms of developing export options for Kazakh oil," Takachakov said by telephone.

The consortium owns a 1,580-kilometer pipeline from the Tengiz field in western Kazakhstan to Russia's port of Novorossiisk on the Black Sea. The pipeline pumped 32.6 million tons of oil in 2007, and its owners plan to double the pipeline's capacity in the next five years.

But Transneft, which holds Russia's 24 percent CPC stake, said Wednesday that it also was considering building a parallel line -- a move that would help Russia and Kazakhstan but contradict the interests of other shareholders, spokesman Igor Dyomin said, Interfax reported. Another option, he said, would be bankrupting the heavily indebted venture.

Kazakhstan had been interested in purchasing part of a 7 percent share in CPC held by the government of Oman and appeared surprised to find that it had already been sold to Russia.

On Oct. 30, Kazakh President Nursultan Nazarbayev told Prime Minister Vladimir Putin in Astana that the two countries should jointly buy the stake, prompting Putin to respond: "I am not entirely sure, but it seems to me we have already bought it. I need to check."

The CPC web site has not been updated to reflect a sale by Oman. Two people close to the consortium said Thursday that Transneft might not have finalized its purchase of Oman's stake.