Ksenia Galouchko and Anna Shiryaevskaya

TNK-BP gained the most in more than a week as investors speculated BP Plc (BP/)’s billionaire partners in Russia’s third-largest oil producer will enter a bidding war against OAO Rosneft for the U.K. explorer’s entire stake.

TNK-BP jumped 2 percent to 84.3 rubles by the close in Moscow, the biggest advance since Sept. 14. Rosneft, the country’s biggest oil producer, dropped 2.3 percent to 204.18 rubles. BP last traded 1.8 percent lower at 438.05 pence in London. Russia’s Micex Index slumped 2.4 percent.

AAR, the group representing the billionaires, will make a binding cash offer to acquire the U.K. oil producer’s entire 50 percent of the TNK-BP venture rather than the half of BP’s holding it proposed to acquire in July, according to a person with knowledge of the plans, who declined to be identified before the bid is submitted. Rosneft, headed by President Vladimir Putin’s former deputy for energy, Igor Sechin, is seeking as much as $15 billion in loans to buy BP out of the 50-50 venture, two people said Sept. 19.

“The market is hopeful of some kind of bidding war between Rosneft and AAR,” Julian Rimmer, a trader at CF Global Trading, said by e-mail.

TNK-BP’s shares are also climbing on bets the company will preserve its “high” dividends if AAR buys out the stake, Sergey Vakhrameev, an analyst at IFC Metropol in Moscow, said by phone.

The shareholders of TNK-BP approved a full-year dividend of 9.96 rubles (32 cents) per common and preferred share for 2011. That’s in addition to the 3.41 rubles a share TNK-BP Holding (TNBP) paid out for the first half of 2011, the Moscow-based company said in a June 28 statement. State-run Rosneft will pay 7.53 rubles a share in 2011 dividends, the company said on Sept. 18 in a regulatory filing.

“Although Rosneft as a state-owned company has more money to win the bidding, some investors are hopeful that if AAR wins, they will keep the high dividends,” Vakhrameev said.

http://www.bloomberg.com/news/2012-09-26/tnk-bp-gains-after-billionaires-said-to-expand-bid-moscow-mover.html