Igor Sechin, the top executive at state-owned oil company Rosneft, said the company is expected to finalize an agreement with AAR, which represents Russian interests in the joint venture with BP, in the coming weeks.
"I think we'll sign a binding agreement with AAR in December," he was quoted by Russia's state-run news agency RIA Novosti as saying.
He said the move doesn't require the approval of Rosneft shareholders. Shares in TNK-BP were up 6 percent in Friday trading after Sechin said Rosneft would "keep and develop" the TNK-BP brand of retail gasoline stations in Russia and Ukraine.
Rosneft reached a deal with BP to buy its half of TNK-BP for more than $17 billion in cash. A separate deal outlines Rosneft's acquisition of the 50 percent stake in the venture held by Alfa-Access-Renova for $28 billion.
BP's Chief Executive Office Bob Dudley, the former head of TNK-BP, said the agreement with Rosneft removed "considerable uncertainty" for his shareholders.