Russian oil company Yukos’s boss Steven Theede has announced his company’s position is unsustainable and it can no longer continue to operate normally following a fresh back tax claim form the Kremlin for five and a quarter billion euros. Added to existing claims , it means Yukos has to find 11 billion euros, double its market capitalisation.Shareholders will meet on December the 20th. to decide if the company is to file for bankruptcy or go into liquidation. The news further depressed the share price, which has now lost 25 percent this week, and is 80 percent down on its April peak. Some analysts say this means Yukos is effectively worthless, with assets unable to cover liabilities.