KIEV, Nov. 2 - Ukraine’s largest oil refinery, UkrTatNafta, is on the verge of a bankruptcy that may have been prepared and could benefit Russian shareholders, the refinery’s recently reinstated top manager said, citing financial data.

Pavlo Ovcharenko, reinstated as UkrTatNafta’s CEO by a court ruling a week ago, in a letter to the Ukrainian security service on Friday accused Russian oil company Tatneft of driving the refinery to the bankruptcy.