Aug. 4 (Bloomberg) -- TNK-BP Chief Financial Officer James Owen quit, saying a dispute between BP Plc and its billionaire partners in the Russian oil venture makes it difficult for him to work independently, as his role demands.

Owen tendered his resignation to Chief Executive Officer Robert Dudley today, the company said in an e- mailed statement. He will leave at the end of this month.

TNK-BP, a 50-50 venture between BP and a group of billionaires known collectively as AAR, is embroiled in a dispute over strategy and management. BP, which relies on the company for almost a quarter of its production, is struggling to maintain control of the company.

``I greatly regret that we are losing Jim,'' Dudley said in the statement. ``He will be very hard to replace.''

Dudley, 52, left Russia last month citing ``sustained harassment'' in receiving permission to work in Russia and performing his duties.

BP CEO Tony Hayward and billionaire Mikhail Fridman met in Prague on July 30 to seek a resolution to the dispute after the battle for control of the company, Russia's third-biggest crude producer, intensified last month.

The investors in the venture are Fridman and fellow billionaires German Khan, Viktor Vekselberg and Len Blavatnik. Fridman and Vekselberg have said BP treats TNK-BP like a subsidiary and has constrained growth, which BP denies.

Workers Depart

Hayward said July 29 that BP won't be ``intimidated by strong-arm tactics'' and vowed to defend its rights at TNK-BP.

BP last month pulled its remaining 60 employees contracted to work at the venture from Russia, as a minority shareholder in TNK-BP's traded unit sought to overturn the agreement covering their services. Vekselberg, a TNK-BP executive as well as shareholder, demanded last week that the vacancies be filled.

BP shares rose 7.5 pence, or 1.4 percent, to 528.75 pence at 10:39 a.m. in London after today's statement.

Dudley may step down as CEO under a possible deal to resolve differences between BP and its Russian partners, the Wall Street Journal reported Aug. 1, citing people involved on both sides in negotiations.

BP would also agree to a revision of profit-sharing, and in return Vekselberg and Khan would give up their management roles, the Journal said. The Financial Times carried a similar report the following day.

Stan Polovets, who represents the billionaire shareholders in TNK-BP, said on Aug. 1 nothing had been agreed, when asked about the talks between Hayward and Fridman. ``The meeting was a first step but there are many difficult issues that need to be resolved.''

To contact the reporter on this story: Lucian Kim in Moscow at lkim3@bloomberg.net

Last Updated: August 4, 2008 05:58 EDT