Moscow, Russian Federation – Mobile TeleSystems OJSC (“MTS” – NYSE: MBT), the leading telecommunications provider in Russia and the CIS, announces that “COMSTAR – United TeleSystems” JSC (“Comstar” – LSE: CMST), a majority-owned subsidiary of MTS, issued a release informing that, following the announcement on December 24, 2010 that Comstar shareholders had approved the merger of Comstar into MTS pursuant to which Comstar will cease to exist as a separate legal entity, Comstar intends to cancel the listing of the global depositary receipts (“GDRs”) representing ordinary shares in Comstar from the Official List of the UK Listing Authority and cancel the admission of the GDRs to trading on the London Stock Exchange (the “GDR Delisting”).

The statutory merger of Comstar into MTS under Russian law is conditional upon certain statutory merger procedures that include filings with, and actions by, various government agencies.

The GDR Delisting is currently expected to take place on 25 March 2011 or shortly afterwards, but is subject to the completion of such statutory merger procedures.

For additional information, please visit Comstar’s corporate website at: https://comstar.ru/en/news_center/pressreleases/.