Mikhail Gutseriyev, RussNeft's ex-president, is wanted for fraud and tax evasion, and is said to be residing in Turkey. He resigned from his post in the summer.
Earlier this month the Moscow City Court upheld an arrest warrant for the fugitive tycoon, and a ruling to freeze 100% of RussNeft's shares. The court also banned any transactions with the frozen shares.
If tried and convicted, Gutseriyev faces up to six years in prison, in a case reminiscent of legal battles for the now bankrupt oil firm Yukos.
BasEl, owned by Kremlin-friendly tycoon Oleg Deripaska, is seeking to buy Gutseriyev's former company.
BasEl is awaiting a decision from the anti-monopoly authorities on the deal.
RussNeft owns 30 oil producing companies, three oil refineries, two transport companies and a network of 300 gas filling stations.
