Surprise for “MTS Connect Unlimited” and “MTS Connect Unlimited+” package subscribers High-speed Internet volumes provided within “MTS Connect Unlimited” and “MTS Connect Unlimited+” packages double April 13, 2011, Yerevan, Armenia – VivaCell-MTS, a subsidiary of “Mobile TeleSystems” OJSC, is glad to announce that the volume of the high-speed Internet provided each month within “MTS Connect Unlimited” package has doubled. Instead of the 5GB provided before, which included both download and upload traffic, the subscriber now receives separate 5GB of high-speed Internet for download and 5GB for upload. Similarly, subscribers of “MTS Connect Unlimited+” package get 10GB of high-speed Internet for download and 10GB - for upload, instead of the total of 10GB provided before for both. For more information please visit www.vivacell.am, contact 111 free of charge hotline, chat with us through “111 Online”, or approach one of our 105 service centers across Armenia. Be ready for more! VivaCell-MTS... More than operator! VivaCell-MTS (K-Telecom CJSC) is Armenia’s leading mobile operator, having the widest 2G/ 3G network reach and spreading a wide range of Voice and Data services all across Armenia. Having the best of the Armenian people interest at heart since its launch on 1st July 2005 and in a short period of time VivaCell-MTS has managed to build a nationwide network and a considerable customer base. VivaCell-MTS drives innovation and aims at always being at the forefront of any development serving the Armenian mobile communications market. For more information, visit www.vivacell.am * * * Mobile TeleSystems OJSC (“MTS”) is the largest mobile phone operator in Russia and the CIS. Together with its subsidiaries, the Company services over 100 million subscribers. The regions of Russia, as well as Armenia, Belarus, Turkmenistan, Ukraine, and Uzbekistan, in which MTS and its associates and subsidiaries are licensed to provide GSM services, have a total population of more than 230 million. Since June 2000, MTS’ Level 3 ADRs have been listed on the New York Stock Exchange (ticker symbol MBT). Additional information about MTS can be found at www.mts.ru

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