Moscow, Russian Federation – Mobile TeleSystems OJSC (“MTS” – NYSE: MBT), the leading telecommunications provider in Russia and the CIS, announces the submission results of MTS’ Voluntary Tender Offer (“VTO”) to acquire up to 37,614,678 COMSTAR – United TeleSystems JSC (“Comstar” – LSE: CMST) ordinary shares. The VTO closed on September 21, 2010 for Comstar shareholders. VTO applications have been submitted for a total of 125,215,743 Comstar shares (including shares underlying Global Depositary Receipts, “GDRs”), representing 29.96% of Comstar’s issued share capital.

The VTO has been oversubscribed by approximately 3.3289 times on the basis of applications received. As a result, MTS will purchase Comstar shares based on the ratio of 37,614,678/125,215,743 (the “Pro Rata Ratio”), or approximately 0.3004 of a Comstar share for each Comstar share or GDR tendered.

Comstar shareholders subscribing to the VTO are recognized in accordance with Russian law as having entered into sale and purchase agreements with MTS. The number of shares to be purchased from any Comstar shareholder subscribing to the VTO is equal to the amount of shares set forth in the shareholder’s application multiplied by the above Pro Rata Ratio (the “Purchase Amount”). Comstar’s registrar, OJSC “Reestr” (the “Registrar”) will send out to each Comstar shareholder subscribing to the VTO a mail notification specifying the Purchase Amount. Each Comstar shareholder subscribing to the VTO is required to execute and deliver a transfer order for the Purchase Amount to the Registrar, with the Purchase Amount to be credited to MTS’ personal account with the Registrar no later than October 6, 2010 (inclusive). Subscribing shareholders are urged to transfer the Purchase Amount as soon as practicable to avoid late delivery. Deutsche Bank Trust Company Americas is the depositary bank for Comstar’s GDR facility and will process the required documentation on behalf of participating Comstar GDR holders.

Payment for the shares to be purchased in the VTO will be made within 15 days from the moment the shares are credited to MTS’ personal account with the Registrar.

On July 13, 2010 Comstar received the VTO from MTS to acquire up to 37,614,678 Comstar ordinary shares that MTS and its affiliated persons do not already own for RUR 220.0 per Comstar share. The number of ordinary shares to be purchased in the VTO is up to 9.0% of Comstar’s issued share capital, and includes shares underlying Comstar GDRs. MTS owns 61.97% of Comstar, or 64.03% when excluding treasury shares, and consolidates Comstar in its financial results.

MTS has sufficient available cash, cash equivalents and undrawn financing commitments to purchase the shares in the VTO and has a bank guarantee in this respect from Sberbank, as required by the applicable rules regarding VTOs.

Goldman Sachs International is acting as financial advisor to MTS and Latham & Watkins LLP is acting as legal advisor to MTS.

Documentation regarding the MTS VTO to acquire Comstar shares is available at https://www.mtsgsm.com.