M obile T ele S ystems

1. Mobile TeleSystems Financial and Operational Results First Quarter Ended March 31, 2003 June 26, 2003 Internet site: www.mtsgsm.com/ir email address: ir@mts.ru

2. 2003: Implementing the strategy *According to AC&M-Consulting as of May 31, 2003

3. Income Statement Highlights • MTS reports strong top line and bottom line growth Revenue EBITDA Net income 80% 82% 87% 446.1 224.8 80.2 US$ mln 123.5 247.6 42.8 Q1 02 Q1 03 Q1 02 Q1 03 Q1 02 Q1 03 Revenues were boosted mainly by organic growth of MTS business MTS maintains EBITDA margin of 50% Strong net earnings growth Source: MTS Note: See Attachment A for definitions of EBITDA and EBITDA margin and a reconciliation of both financial measures.

4. Strong Subscriber Growth • MTS is a market leader in Russia and the CIS with over 11.23m subs as of June 25, 2003 • MTS together with its subsidiaries currently operates in Russia (9.23m subs) and Ukraine (1.99m subs) • MTS’ 49%-owned joint venture in Belarus services around 165,000 customers UMC contributes 2 mln users to MTS subs base Source: MTS

5. The Booming Market • The mobile population in Russia grew by 10m in 2002 and by an additional 5.3m in the first five months of 2003 to 23.5m, fueled by a growing economy and a greater demand for telecommunications services. Mobile penetration is currently at 16%* Source: AC&M-Consulting *According to AC&M-Consulting as of May 31, 2003

6. #1 Provider in Russia • MTS continues to be the market leader in the Russian market with a 37%* market share • MTS market share in the Moscow market has increased from 43% at year-end 2002 to 46% at the end of May 2003* • The Company’s strategic objective is to remain as the leading mobile phone operator in Russia both in terms of revenues and number of subscribers *According to AC&M-Consulting as of May 31, 2003

7. Tapping the market in Ukraine • At the end of Q1 2003 UMC, MTS’ subsidiary in Ukraine, had 1.82 million subscribers of which around 71% were using pre-paid services • The company provided services to around 2 million subscribers as of June 25, 2003 • As of end of May 2003, UMC controlled around 45% of the cellular market in Ukraine* *According to Ukrainian News as of May 31, 2003

8. Building the footprint in Belarus • MTS’ unconsolidated subsidiary started operations in Belarus in June 2002 and has so far built a market share of 21%* competing against the only incumbent GSM operator *According to AC&M-Consulting as of May 31, 2003

9. Breakdown by Regions Source: MTS

10. Developing the Infrastructure • At the end of Q1 2003, MTS together with its consolidated subsidiaries operated 6,142 base stations and 72 switches • In addition, MTS’ joint venture in Belarus operated 242 base stations and one switch Number of Base Stations Number of Switches UMC had 8 switches UMC had 1,320 base stations Source: MTS Source: MTS

11. Licences Coverage • As of June 25, 2003 MTS’ GSM licences covered a population of • 169.2m, including 110.2m in Russia, 10m in Belarus • and 49m in Ukraine Murmansk Anadyr Kaliningrad St. Petersburg # Petrozavodsk Arkhangelsk Pskov Naryan-Mar Novgorod Vologda Tver Smolensk Minsk Yaroslavl Syktyvkar Moscow Kostroma Kaluga Salekhard Ivanovo Bryansk Kirov Tula Vladimir Кiev Kudymkar Orel Ryazan Kursk N. Novgorod Khanty-Mansiysk Lipetsk Izhevsk Belgorod Tambov Perm Voronezh Kazan Ekaterinburg Saratov Ufa Tumen Rostov-on-Don Samara Chelyabinsk Kurgan Krasnodar Omsk Orenburg Maikop Elista Novosibirsk Barnaul Blagoveschensk Gorno-Altaysk Yuzhno-Sakhalinsk Kyzyl Khabarovsk Source: MTS

12. Profitability of Regions • MTS operations in the regions of Russia added $18.9 million to the • Company’s bottom line in Q1 2003 Source: MTS Note: MTS has consolidated UMC from March 1, 2003 MTS’ business is organized on a geographical operations basis. Performance is measured and reported based on operating income by legal entity. Currently, MTS reports operations in Russia in two segments: MTS OJSC and Rosico (“Moscow Segment”) and all other legal entities in Russia combined. The Moscow Segment includes operations in the Moscow license area in addition to operations in Ivanovo, Kirov, Kaluga, Kostroma, Komi Republic, Kurgan, Nizhny Novgorod, Orenburg, Perm, Ryazan, Pskov, Saratov, Smolensk, Tambov, Tula, Tumen, Tver, Vladimir, Chelyabinsk, and Yaroslavl. The second geographical segment includes all of our other Russian legal entities not included above, most notably our operation in the north-west of Russia, including St. Petersburg, and southern Russia, including Krasnodar.

13. Key Operating & Financial Data • MTS Operations in Russia • MOU - Usage per subscriber decreased in Q1 2003 largely because of seasonal factors • ARPU - continued to decline partially as a result of decreased usage but also as a result of an increase in the number of mass-market subscribers in the subscriber mix • Churn - the general market trend of growing churn continued during Q1 2003. Today, programs aimed at encouraging customer loyalty have become increasingly important for the Company Source: MTS

14. SAC Breakdown • SAC per gross subs addition in Russia continued to decline in 2003 reflecting the lower cost of attracting mass-market subscribers (in particular, the lower commissions paid to dealers for Jeans subscribers) Source: MTS

15. Key Operating & Financial Data • MTS Operations in Ukraine Source: MTS

16. Disclaimer • Some of the information in this presentation 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. You can identify forward looking statements by terms such as “expect,” “believe,” “anticipate,” “estimate,” “intend,” “will,” “could,” “may” or “might” the negative of such terms or other similar expressions. 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 statements to reflect events and circumstances occurring after preliminary offering memorandum dated as of January 28, 2003 and to reflect the occurrence of unanticipated events. 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 20-F. 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.

17. Attachment A • EBITDA should not be considered in isolation as an alternative to net income, operating income, net cash provided by operating activity or any other measure of performance under U.S. GAAP. We believe that EBITDA is viewed as a relevant supplemental measure of performance in the wireless telecommunications industry and we define EBITDA as operating income excluding depreciation and amortization. EBITDA margin is defined as EBITDA as a percentage of our net revenues. We believe EBITDA and EBITDA margin to be relevant and useful information as these are one of important measurements used by our management to measure the operating profits or losses of our business. EBITDA is also one of many factors used by the credit rating agencies to determine our credit ratings. EBITDA and EBITDA margin should be considered in addition to, but not as a substitute for, other measures of financial performance reported in accordance with accounting principles generally accepted in the United States of America. EBITDA and EBITDA margin, as we have defined them, may not be comparable to similarly titled measures reported by other companies, who may refer to EBITDA as Adjusted EBITDA. EBITDA is often calculated by adjusting net income to exclude only depreciation and amortization, income taxes and interest. If EBITDA were so calculated it would have been: $211.5 million, $116.5 million, $172.0 million for Q1 2003, Q1, 2002 and Q4 2002, respectively. • The following table provides a reconciliation of EBITDA to operating income:

18. Attachment A (continued) • The following table provides a reconciliation of EBITDA margin to operating income as a percentage of net revenues: • If the Company were to reconcile EBITDA to net income, following would be the reconciliation: