Moscow, Russian Federation — August 30, 2005 — Mobile TeleSystems OJSC (“MTS” — NYSE: MBT), the largest mobile phone operator in Russia and the CIS, today announces excellent financial and operating results for the second quarter of 20051 featuring strong financial performance, robust subscriber growth and ARPU increase.

Moscow, Russian Federation – June 1, 2005 – Mobile TeleSystems OJSC (“MTS” — NYSE: MBT), the largest mobile phone operator in Russia and the CIS, today announces its first quarter 2005¹ financial and operating results.

Moscow, Russian Federation — March 22, 2005 — Mobile TeleSystems OJSC (“MTS” — NYSE: MBT), the largest mobile phone operator in Russia and the CIS, today announces its fourth quarter and full-year 20041 financial and operating results.