OREANDA-NEWS. Mobile TeleSystems OJSC ("MTS" — NYSE: MBT), the largest mobile phone operator in Russia and the CIS, announces that Moody&$146;s Investors Service has upgraded the corporate family and existing bond ratings of MTS to Ba2 from Ba3. The outlook on the ratings is positive.

In a press release circulated, Moody’s remarks: [t]he upgrade reflects (i) the company’s robust operational and financial performance in the second half of 2006 and six months of 2007; (ii) its demonstrated ability to sustain its market share in Russia, strong positions in Ukraine and a number of other CIS countries; (iii) free cash flow generation in the first half of 2007; (iv) significantly improved profitability metrics, (v) modest leverage below 1.0x Total Adjusted Debt to reported EBITDA on an annualized six months basis, (vi) a relatively conservative and consistent management strategy as regards acquisition activities; and (vii) a higher level of predictability in the company’s financial policies over the past 12 months.

In addition, Moody’s added, "Given the positive outlook, a future upgrade remains a strong possibility."

Please refer to www.moodys.com for additional information.