The Verkhnechonskoye field in eastern Siberia is expected to give out 7-10 tons of oil per year
Verkhnechonskoye is operated by VerkhnechonskNefteGaz, in which TNK-BP owns 68 percent and Rosneft owns 26 percent.
Under a 2007 agreement, the two firms were to purchase the stake on an equal basis. But Rosneft first vice president Sergei Kudryashov said to reporters that the company has not ruled out increasing its stake in the operator.
Crude from the field will initially flow southwest through the pipeline to the Angarsk refinery owned by Rosneft because the eastern stretch of the pipeline to the Pacific is not yet ready.