The Imperial Energy board said the offer by Gazprombank is currently being reviewed and "there is no certainty that any agreement will be entered into."
Last week, the company said an investor offered a below market price for its shares, which brought Imperial Energy stock down 1.7% to 13.53 pounds ($27), and then further down to 13.31 pounds ($26.62).
Russia's natural resources ministry said previously there was a considerable discrepancy in the company's claimed oil reserves.
According to Imperial Energy's reserve audit data as of December 31, 2006, the company's "proven plus probable" reserves amount to 802.6 million barrels. Imperial Energy plans to produce 10,000 barrels per day by late 2007, 25,000 bbl/d by late 2008, and 35,000 bbl/d by late 2009.
Imperial Energy said it had invested $600 million in the development of its oil deposits in Russia.
Founded in 1990, Gazprombank, a subsidiary of Russian energy giant Gazprom [RTS: GAZP], which has about 2 million retail clients and over 36,000 corporate clients, is one of the top five banks in Central and Eastern Europe, with assets totaling 1.088 trillion rubles ($43 billion) and equity capital of 88.3 billion rubles ($3.5 billion) as of April this year.