UPDATE 1-Small Russia oil firm seen changing hands for debt

*Timan could be latest Russian oil asset seized for debt

*Credit Suisse sold stake and options to investor Redbell

*Timan CEO says Redbell represents tycoon Alexander Lebedev (Adds Timan CEO on Redbell's backers, comment from NRB)

MOSCOW, June 1 (Reuters) - A small Russian oil explorer, AIM-listed Timan Oil & Gas (TMAN.L), may be seized for debts after its core owner received a notice of default, the company said on Monday.

Timan would follow Urals Energy (UEN.L), a mid-sized producer which ceded its main production assets to state controlled Sberbank (SBER03.MM).

Investors are also closely watching the case of Sibir Energy (SBE.L), whose core shareholders have pledged their stakes with Sberbank, and which is suing one of the shareholders to reclaim $400 million advanced in a failed real estate deal.

Timan said that Credit Suisse had sold 13.88 percent of the company and a series of options to Redbell, a company controlled by businessman Vitaly Belik.

They included a cash option for a stake equivalent to about 8.5 percent and a put and call option on 13.88 percent allowing the holder to resell it to a group of investors led by Chief Executive Alexander Kapalin.

The option holder would be awarded an additional 48.3 percent stake in Timan if the option was not honoured.

"On May 29 (Redbell) served notice on Alexander Kapalin that he is in default," Timan said. "As a result it is possible that ownership of the 82,508,336 ordinary shares as described above will pass to Redbell.

Kapalin told Reuters by telephone that Credit Suisse told him Belik represented National Reserve Bank, owned by banking and industry magnate Alexander Lebedev, who bought a majority interest in London's Evening Standard this year (DMGOa.L).

"We are trying to come to an agreement with Redbell," he said. "If not, Redbell can get over 50 percent of Timan shares."

A spokesman for National Reserve said the bank was a lender to Timan in partnership with a Western bank, which he declined to identify, and had exercised its right to the collateral.

Credit Suisse was not immediately available for comment.

Belik, an executive at government investment firm Russian Venture Co., confirmed that he was correctly identified in the news release but declined to comment by telephone.

The company has already agreed to pledge more than 51 percent of shares with Kazakh businessman Timur Kuanyshev against a $100 million loan, with the right to convert the loan into equity. (Reporting by Katya Golubkova and Oksana Kobzeva; Editing by David Cowell and Gunna Dickson)