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MOSCOW, July 30 (RIA Novosti) - The board of directors of one of Russia's top 10 oil and gas producers, RussNeft, has approved the resignation of its CEO, Mikhail Gutseriyev.

The board appointed Senior Vice President Oleg Gordeyev as the company's acting president.

The company confirmed in a press release that structures affiliated with the pro-Kremlin industrial holding Basic Element, controlled by billionaire Oleg Deripaska, applied July 27, 2007 to the Federal Anti-Monopoly Service for permission to acquire a controlling stake in RussNeft. Under Russian law, the service must make a decision within three months.

The Interior Ministry said in mid-May that Gutseriyev was charged with illegal business practice and tax evasion. RussNeft offices were searched and Gutseriyev questioned as a witness. He faces up to six years in prison if convicted.

Gutseriyev denied any charges have been formally brought against him.

He said the allegations apparently concerned a "surplus" 60,000 metric tons of oil produced by a company subsidiary, adding that next to the 15 million tons of its annual output it was a very small amount.

Gutseriyev is 31st on the Forbes list of the world's richest people, with a personal wealth of $3 billion.

According to the business daily Vedomosti, Gutseriyev's problems stem from his conflict with the Kremlin and the reluctance to sell his company. He set himself on a collision course with the Kremlin by buying some of the embattled oil company Yukos' assets shortly before it was declared bankrupt.

The daily quoted informed sources as saying that last year Gutseriyev received an offer to sell his company for $1 billion to a state controlled structure but turned it down, saying the price was ridiculous. Experts put RussNeft at $8-10 billion.

RussNeft, Russia's newest vertically integrated oil company, is among the country's top 10 crude producers, with recoverable reserves exceeding 630 million metric tons (4.6 billion barrels).