Ad Hoc Notice
Moscow, Russian Federation – Mobile TeleSystems OJSC (“MTS” – NYSE: MBT), the leading telecommunications provider in Russia and the CIS, announces that on February 9, 2012, MTS received a Request for Arbitration from Mobile TeleSystems Finance SA (“MTS Finance”), wholly owned subsidiary of MTS, which has initiated an arbitration process under a loan agreement ("Loan Agreement") between the parties dated January 28, 2005. Under the terms of the Loan Agreement, MTSF lent $400 million to MTS. MTS Finance seeks the payment of all sums due to it under the Loan Agreement. MTS agrees that arbitration is the correct forum for any dispute between the parties but strongly denies that any sum is still owed by it to MTS Finance.