MTS and Siemens have successfully carried out demonstration of the 3G network — UMTS

Moscow, Russian Federation, December 26, 2001. Mobile TeleSystems OJSC (NYSE: MBT), Russia’s largest cellular operator, and Siemens Information and Communication Mobile (IC Mobile) have successfully demonstrated an operating fragment of a 3G UMTS test network. The practical demonstration included voice calls between mobile terminal devices and between mobile terminal devices and ISDN phones, data transmission and the possibilities of 3G applications.

MTS Enters Debt Market

Moscow, Russian Federation — 24 December 2001 — Mobile TeleSystems OJSC (“MTS”) has issued a USD 250 million three-year Eurobond through its wholly owned subsidiary Mobile TeleSystems Finance S.A.

Contact investor relations:

+ 7 495 223 20 25 ir@mts.ru

MTS Investor Relations
App for iPad