Moscow, Russia - December 29, 2005 - Sistema (LSE: SSA) the largest private sector consumer services company in Russia and the CIS, announced today that the Moscow Arbitration Court dismissed the lawsuit filed by Open Joint Stock Company ASVT ("AVST") against Sistema on October 12, 2005 for approximately 50 billion rubles (US$1.75 billion at the exchange rate on October 12, 2005).As previously announced, the lawsuit related to Sistema's investment in Mobile TeleSystems OJSC ("MTS") made over ten years ago.