Moscow, Russian Federation – Mobile TeleSystems OJSC (“MTS” – NYSE: MBT), the leading telecommunications operator in Russia and the CIS, announces that Fitch Ratings has affirmed MTS’s Long-Term Issuer Default Rating at ‘BB+’ while removing all ratings from Rating Watch Negative. The Outlook on the Issuer Default Rating is Stable.

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For further information, please contact in Moscow:

Joshua B. Tulgan
Director, Department of Corporate Finance and Investor Relations
Mobile TeleSystems OJSC
Tel: +7 495 223 2025
E-mail: ir@mts.ru