Sistema, a Russian conglomerate controlled by entrepreneur Vladimir Yevtushenkov which owns a 50.6% stake in domestic cellco Mobile TeleSystems and shares in other telecoms businesses in Russia, is to forge ahead with plans to float on the London stock market this week. In what could be the biggest flotation of 2005, Sistema is hoping to secure a market valuation of GBP5 billion and plans to ask the City for up to GBP800 million in return for around 20% of the company. If successful, the Russian group will become one of the largest public companies listed in the UK. However, the quotation is seen as a major test of investor confidence in Russia following the recent case of oil giant Yukos, which found itself the subject of a tenacious attack by the Russian state; the successful ‘westernised’ company was broken up and its founder Mikhail Khordorkovsky imprisoned following a demand for more than GBP10 billion in back taxes. Mr Yevtushenkov will still own around 65% of Sistema after the flotation.