Russia's largest oil company, LUKoil, is negotiating to take an equity stake in a struggling joint venture between the U.S. Chevron Corp. and Kazakhstan's government, a LUKoil official said Wednesday.


LUKoil spokesman Pyotr Neyev said talks with the Kazakh side have been under way for several months. He declined to give details on the negotiations.


Interfax on Wednesday cited an unnamed source in the Kazakh Oil and Gas Ministry as saying that LUKoil is looking for a 20 percent share in the joint venture.


Kazakhstan, which now holds 50 percent of the Tengizchevroil venture, is likely to cede most of the stake, the source said.


Dick Pashelka, head of Chevron's Moscow office, said LUKoil so far has dealt mainly with the Kazakh side.


"They have not contacted Chevron with any proposal that would involve numbers," he said.


Interfax also quoted a Kazakh government source as saying the country is seeking talks with Russia early next month to build a pipeline from the Tengiz field to the Black Sea. Foreign companies working in the area would be invited to participate.


Preliminary negotiations between Russian and Kazakh oil officials already have been held, Interfax said.