17 August 2006

MOSCOW, RUSSIAN FEDERATION — AUGUST 17, 2006 — MOBILE TELESYSTEMS OJSC («MTS» — NYSE: MBT), THE LARGEST MOBILE PHONE OPERATOR IN RUSSIA AND THE CIS, IS PLEASED TO ANNOUNCE THE SUCCESS OF ITS $1.33 BILLION SYNDICATED LOAN FACILITY.

On April 21, 2006, the Company signed a syndicated loan facility in the amount of $1.33 billion with leading financial institutions. As stated previously, the loan will be used for debt refinancing, specifically $420 mln of the current syndicated loan, and for corporate needs such as acquisitions.

The level of interest in the facility from the international investors was high, and it was oversubscribed to $1.5 billion. However, in adherence to the Company?s plan for raising additional financing, MTS decided to keep the amount at $1.33 billion.

Mr Vsevolod Rozanov, the Company?s Chief Financial Officer, commented: «The successful placement of the facility demonstrates a high level of confidence on the part of the financial institutions. The size and terms of the loan may set a precedent for other Russian non-raw materials companies seeking additional financing on international financial markets.»

The Mandated Lead Arrangers are: The Bank of Tokyo-Mitsubishi UFJ Ltd., Bayerische Landesbank, HSBC Bank plc, ING Bank  N. V., Raiffeisen Zentralbank Oesterreich AG and Sumitomo Mitsui Banking Corporation Europe Limited. HSBC Bank plc, ING Bank  N. V. and Raiffeisen Zentralbank Oesterreich AG are Bookrunners, with ING Bank  N. V., London Branch acting as the Facility and Documentation Agent. Following successful senior syndication with Credit Suisse International and BNP Paribas that joined as Underwriters and Mandated Lead Arrangers and ABN AMRO Bank  N. V. and WestLB as Mandated Lead Arrangers, 15 additional lenders have participated in general syndication.

The Facility is divided into two tranches. First tranche — $630 mln; maturity — 3 years; annual interest is LIBOR plus 0.80%. Second tranche — $700 mln; maturity — 5 years; annual interest is LIBOR plus 1.00% during the first three years and LIBOR plus 1.15% during the last two years.