Mobile TeleSystems OJSC (NYSE: MBT) is Russia’s leading mobile cellular operator servicing over 3.9 million subscribers. MTS has GSM 900/1800 licenses to provide mobile cellular telephony services in 49 regions of the Russian Federation, covering 93.5 million people or 65% of the country’s population. MTS network has operations in 34 regions of the Central (including Moscow and Moscow region, North-West (including the city of St Petersburg), South, Volga, Urals, Siberia and Far-East macro regions, which covers more than 75.8 million people, or 53% of the population of the Russian Federation. Since June 2000 MTS ADRs are listed on the NYSE under the ticker MBT. Additional information about MTS can be found on MTS’s website at www.mtsgsm.com Standard and Poor’s (www.standardandpoors.com) provides independent financial information services, analytical services and credit ratings for international financial markets. Standard and Poor’s has divisions in 18 countries employing over 5000 people and is an integral part of the world capital market. One of its aims is to provide important analytical data, risk evaluation and information services on the new markets, particularly through an Internet site dedicated to the emerging markets.

Some of the information in this press release may contain projections or other forward-looking statements regarding future events or the future financial performance of MTS, as defined in the safe harbor provisions of the U.S. Private Securities Litigation Reform Act of 1995. We wish to caution you that these statements are only predictions and that actual events or results may differ materially. We do not intend to update these statement to conform them to actual results. We refer you to the documents MTS files from time to time with the U.S. Securities and Exchange Commission, specifically, the Company`s most recent Form F-1. These documents contain and identify important factors, including those contained in the section captioned “Risk Factors,“ that could cause the actual results to differ materially from those contained in our projections or forward-looking statements, including, among others, potential fluctuations in quarterly results, our competitive environment, dependence on new service development and tariff structures; rapid technological and market change, acquisition strategy, risks associated with telecommunications infrastructure, risks associated with operating in Russia, volatility of stock price, financial risk management, and future growth subject to risks.