British oil company BP wants to buy a stake in Russian state-controlled peer Rosneft, adding a new dimension to a long-running struggle for control of a big chunk of the country's oil production.

BP chief executive Bob Dudley and chairman Carl-Henric Svanberg have put the Rosneft proposal to Russian President Vladimir Putin, Rosneft chief executive Igor Sechin said.

The deal would see Rosneft take BP's stake in TNK-BP - a $60 billion joint venture with Russian oligarchs that BP wants to exit. Last year, TNK-BP blocked a deal that would have seen BP and Rosneft explore for oil in the Arctic.

"We are very pleased by this offer. It allows us to fulfil the tenets of cutting the state's stake (in Rosneft), and we are working firmly towards this," said Sechin.

A BP spokesman said: "BP is considering further investment in Russia regardless of who we sell our stake to ... we would be interested in investing some of the proceeds in buying shares in Rosneft", adding that any purchase depended on a sale of its TNK-BP stake going through.

BP is seeking to exit its troubled but lucrative investment in TNK-BP, Russia's third-largest oil company, which it formed nearly a decade ago with four tycoons - Len Blavatnik, Mikhail Fridman, German Khan and Viktor Vekselberg - to tap the country's vast energy reserves.

In July, BP entered a 90-day period to talk to potential buyers including the AAR consortium which represents those tycoons.

Sechin said Rosneft was not in talks with AAR to buy its stake, adding Rosneft has no plans itself to buy shares in BP.

Rosneft's plan to buy BP's TNK-BP stake are progressing and it is talking to banks about raising $15-$20 billion to finance the deal, bankers said.

Kommersant reported a deal being discussed would see Rosneft buy 25 per cent of TNK-BP's shares for $10-$15bn cash with the other 25 per cent paid for with Rosneft shares, leaving BP with a stake of at least 12.5 per cent in Rosneft.-Reuters