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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549


FORM 6-K/A

REPORT OF FOREIGN ISSUER
October 07, 2003
Pursuant to Rule 13a-16 or 15d-16 of
the Securities Exchange Act of 1934

Commission file number: 333-12032


MOBILE TELESYSTEMS OJSC

(Exact name of Registrant as specified in its charter)

Russian Federation
(Jurisdiction of incorporation or organization)

4, Marksistskaya Street
Moscow 109147
Russian Federation
(Address of principal executive offices)


        Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F.

Form 20-F  ý          Form 40-F  o

        Indicate by check mark whether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes  o          No  ý

        This Form 6-K/A amends the Form 6-K filed by Mobile TeleSystems OJSC (the "Company") on August 27, 2003 (the "Form 6-K"), which contained the Company's financial statements for the second quarter of 2003 and a press release announcing the Company's financial results for such period. Certain information contained in both the press release and the financial statement filed as part of the Form 6-K has been affected by a change in the Company's method of consolidation for its subsidiary TAIF Telcom. This Form 6-K/A contains the Company's adjusted financial statements for the second quarter of 2002 and a description of the effect of the adjustment on the Company's financial results for such period.




GRAPHIC


MTS REVISES ITS FINANCIAL INFORMATION
FOR THE SIX MONTHS ENDED JUNE 30, 2003

        Moscow, Russian Federation—October 7, 2003—Mobile TeleSystems OJSC ("MTS"—NYSE: MBT), the largest mobile phone operator in Russia, today announces that the Company revised its previously released financial information for the six months ended June 30, 2003.

        MTS changed its consolidation method for its subsidiary TAIF Telcom, a company providing mobile services in the Tatarstan Republic of Russia. MTS acquired 52.7% of common shares and 50% of preferred shares in TAIF Telcom in April 2003 through a series of transactions for a total of $63.3 million. The Company also signed put and call option agreements in April 2003 to acquire the remaining ownership in TAIF Telcom.

        MTS reviewed the accounting treatment of its call options for the remaining interest in TAIF Telcom and determined that these arrangements should be accounted for in accordance with Emerging Issues Task Force ("EITF") Issue No. 00-4, "Majority Owner's Accounting for a Transaction in the Shares of a Consolidated Subsidiary and a Derivative Indexed to the Minority Interest in That Subsidiary." Accordingly, MTS has decided to account for the Company's call option agreements for the remaining 47.3% of common shares and 50.0% of preferred shares in TAIF Telcom as financing derivatives as the risks and rewards of the additional ownership are maintained by MTS for the duration of the derivatives, notwithstanding the legal ownership of the minority interest. As the result of the change, MTS consolidated 100.0% of TAIF Telcom from April 2003 and reflected the call option purchase price of $49.0 million for the common shares and $10.0 million for the preferred shares as current portion of long-term debt as the Company intends to exercise the call options prior to June 30, 2004. MTS also recognized interest expense of approximately $1.0 million related to these options for the six months ended June 30, 2003. MTS can give no assurance that the acquisition of the remaining interest in TAIF Telcom will be completed on the terms described or at all.

        The change did not impact net revenues, operating income, net income or cash flows of MTS for the three or six months ended June 30, 2003.

2



        The effects of this change on the financial information for the three and six month periods ended June 30, 2003 were as follows (in thousands of U.S. dollars).

 
  As previously
reported

  Adjustments
  As adjusted
At June 30, 2003                  
Licenses and other intangible assets, net   $ 742,588   $ 65,835   $ 808,423
Total assets     3,234,107     65,835     3,299,942
   
 
 
Current portion of long-term debt and capital lease obligations     141,001     59,965     200,966
Total current liabilities     754,564     59,965     814,529
Deferred income taxes     118,347     15,800     134,147
Total long-term liabilities     933,793     15,800     949,593
Total liabilities     1,688,357     75,765     1,764,122
Minority interest     142,454     (9,930 )   132,524
Total liabilities and shareholders' equity   $ 3,234,107   $ 65,835   $ 3,299,942
   
 
 
For the six months ended June 30, 2003                  
Interest expense   $ 41,848   $ 965   $ 42,813
Total other expenses, net     33,880     965     34,845
Income before provision for income taxes and minority interest     342,564     (965 )   341,599
Minority Interest   $ 37,410   $ (965 ) $ 36,445
   
 
 
For the three months ended June 30, 2003                  
Interest expense   $ 23,036   $ 965   $ 24,001
Total other expenses, net     18,050     965     19,015
Income before provision for income taxes and minority interest     208,036     (965 )   207,071
Minority Interest   $ 23,569   $ (965 ) $ 22,604
   
 
 

        For further information contact:

     
Mobile TeleSystems, Moscow    
Investor and Public Relations   tel: +7095 911 6553

Andrey Braginski

 

e-mail: ir@mts.ru

***

        These materials are not an offer for sale of any securities in the United States. Any securities may not be offered or sold in the United Sates absent registration or an exemption from registration under the U.S. Securities Act of 1933, as amended.

        This communication is not an offer to any person in the United Kingdom, or an invitation to any person in the United Kingdom to make offers, to purchase any securities. This communication is directed only at (i) persons who are outside the United Kingdom or (ii) investment professionals falling within Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2001 (the "Order") and (iii) high net worth entities, and other persons to whom it may lawfully be communicated, falling within Article 49(2) of the Order (all such persons together being referred to as "relevant persons"). Any investment activity to which this communication relates will only be available to and will only be engaged with, relevant persons. Any person who is not a relevant person should not act or rely on this document or any of its contents. Stabilization/FSA.

        This press release is not a public offer or advertisement of securities in the Russian Federation, and is not an offer, or an invitation to make offers, to purchase any securities in the Russian Federation.

***

3


        Mobile TeleSystems OJSC (or "MTS") is the largest mobile phone operator in Russia in terms of subscribers. Together with its subsidiaries, the company services over 13.9 million subscribers. The regions of Russia as well as in Belarus and Ukraine in which MTS and its subsidiaries are licensed to provide GSM services have a total population of approximately 185.1 million. Since June 2000, MTS' shares have been listed on the New York Stock Exchange with the ticker symbol MBT. Additional information about MTS can be found on MTS' website at www.mtsgsm.com.

***

        Some of the information in this press release may contain projections or other forward-looking statements regarding future events or the future financial performance of MTS, as defined in the safe harbor provisions of the U.S. Private Securities Litigation Reform Act of 1995. You can identify forward looking statements by terms such as "expect," "believe," "anticipate," "estimate," "intend," "will," "could," "may" or "might" the negative of such terms or other similar expressions. We wish to caution you that these statements are only predictions and that actual events or results may differ materially. We do not intend to update these statements to reflect events and circumstances occurring after the date hereof or to reflect the occurrence of unanticipated events. We refer you to the documents MTS files from time to time with the U.S. Securities and Exchange Commission, specifically, the Company's most recent Form 20-F. These documents contain and identify important factors, including those contained in the section captioned "Risk Factors," that could cause the actual results to differ materially from those contained in our projections or forward-looking statements, including, among others, potential fluctuations in quarterly results, our competitive environment, dependence on new service development and tariff structures; rapid technological and market change, acquisition strategy, risks associated with telecommunications infrastructure, risks associated with operating in Russia, volatility of stock price, financial risk management, and future growth subject to risks.

***

4


        Appendix A


MOBILE TELESYSTEMS

CONDENSED UNAUDITED CONSOLIDATED BALANCE SHEETS

AT DECEMBER 31, 2002 AND JUNE 30, 2003

 
  December 31
2002

  June 30
2003

 
 
  (Amounts in thousands of U.S. dollars, except share amounts)

 
               
CURRENT ASSETS:              
  Cash and cash equivalents   $ 34 661   $ 113 561  
  Short-term investments     30 000     30 000  
  Trade receivables, net     40 501     82 929  
  Accounts receivable, related parties     3 569     4 284  
  Inventory     41 386     56 443  
  Prepaid expenses and other current assets     208 213     279 423  
   
 
 
    Total current assets     358 330     566 640  

PROPERTY, PLANT AND EQUIPMENT, NET

 

 

1 344 633

 

 

1 866 543

 
INTANGIBLE ASSETS, NET     525 009     808 423  
INVESTMENTS IN AND ADVANCES TO AFFILIATES     34 034     51 207  
OTHER ASSETS     21 290     7 129  
   
 
 
    Total assets   $ 2 283 296   $ 3 299 942  
   
 
 
CURRENT LIABILITIES:              
  Accounts payable   $ 117 623   $ 161 077  
  Accrued expenses and other     213 291     446 904  
  Accounts payable, related parties     4 968     5 582  
  Current portion of long-term debt, capital lease and finance obligations     88 330     200 966  
   
 
 
    Total current liabilities     424 212     814 529  

LONG-TERM LIABILITIES

 

 

 

 

 

 

 
  Long-term debt     358 914     769 067  
  Capital lease and finance obligations     7 241     7 237  
  Deferred income taxes     105 818     134 147  
  Deferred revenue and other     19 694     39 142  
   
 
 
    Total long-term liabilities     491 667     949 593  
  Total liabilities     915 879     1 764 122  

COMMITMENTS AND CONTINGENCIES

 

 

 

 

 

 

 

MINORITY INTEREST

 

 

65 373

 

 

132 524

 

STOCKHOLDERS' EQUITY:

 

 

 

 

 

 

 
  Common stock: (2,096,975,792 shares with a par value of 0.1 rubles authorized and 1,993,326,138 shares issued as of June 30, 2001 and December 31, 2000, 345,244,080 of which are in the form of ADS)     50 558     50 558  
  Treasury stock (9,966,631 common shares at cost)     (10 206 )   (10 206 )
  Additional paid-in capital     558 102     558 762  
  Unearned compensation     (212 )   (212 )
  Shareholder receivable     (34 412 )   (31 087 )
  Retained earnings     738 214     835 481  
   
 
 
    Total shareholders' equity     1 302 044     1 403 296  
  Total liabilities and stockholders' equity   $ 2 283 296   $ 3 299 942  
   
 
 

5



MOBILE TELESYSTEMS

CONDENSED UNAUDITED CONSOLIDATED STATEMENTS OF OPERATIONS

FOR THE THREE MONTHS ENDED JUNE 30, 2002 AND 2003
AND SIX MONTHS ENDED JUNE 30, 2002 AND 2003

 
  Three months ended June 30
  Six months ended June 30
 
 
  2002
  2003
  2002
  2003
 
 
  (Amounts in thousands of U.S. dollars, except share and per share data)

 
                           
OPERATING REVENUES                          
  Service revenues, net   $ 294 314   $ 571 375   $ 522 386   $ 992 673  
  Connection fees     5 687     8 852     12 228     16 166  
  Equipment revenues     16 297     25 812     29 288     43 295  
   
 
 
 
 
      316 298     606 039     563 902     1 052 134  
   
 
 
 
 
OPERATING EXPENSES                          
  Interconnection and line rental     31 366     44 508     55 081     78 908  
  Roaming expenses     11 597     24 726     28 713     45 269  
  Cost of equipment     20 001     45 754     38 119     73 639  
  Operating expenses     51 826     88 219     91 672     168 944  
  Sales and marketing expenses     39 494     77 828     64 795     135 564  
  Depreciation and amortization     49 089     99 584     90 678     174 774  
   
 
 
 
 
      203 373     380 619     369 058     677 098  
   
 
 
 
 
  Net operating income     112 925     225 420     194 844     375 036  

CURRENCY EXCHANGE AND TRANSLATION LOSSES (GAINS)

 

 

(141

)

 

(666

)

 

690

 

 

(1 408

)

OTHER EXPENSES (INCOME):

 

 

 

 

 

 

 

 

 

 

 

 

 
  Interest income     (2 093 )   (5 591 )   (5 497 )   (8 823 )
  Interest expenses     11 084     24 001     20 687     42 813  
  Other expense     864     605     2 721     855  
   
 
 
 
 
  Total other expenses, net     9 855     19 015     17 911     34 845  
  Income before provision for income taxes and minority interest     103 211     207 071     176 243     341 599  
PROVISION FOR INCOME TAXES     28 039     55 943     53 954     96 412  
MINORITY INTEREST     10 389     22 604     14 688     36 445  
   
 
 
 
 
NET INCOME   $ 64 783   $ 128 524   $ 107 601   $ 208 742  
   
 
 
 
 
Earnings per share—basic and diluted     0.033     0.065     0.054     0.105  

6



FOR THE SIX MONTHS ENDED JUNE 30 2002 AND JUNE 30, 2003

 
  Six months ended June 30
  Six months ended June 30
 
 
  2002
  2003
 
 
  (Amounts in thousands of U.S. dollars)

 
               
CASH FLOWS FROM OPERATING ACTIVITIES:              
Net income   $ 107,601   $ 208,742  
Adjustments to reconcile net income to net cash provided by operating activities:              
  Minority interest     14,688     36,445  
  Depreciation and amortization     90,678     174,774  
  Amortization of deferred connection fees     (12,228 )   (16,166 )
  Provision for obsolete inventory     1,572     3,278  
  Provision for doubtful accounts     2,850     22,851  
  Loan interest accrued     20,827     42,813  
  Loan interest paid     (19,674 )   (25,969 )
  Deferred taxes     (3,375 )   (17,064 )
  Non-cash expenses associated stock bonus and stock options              
Changes in operating assets and liabilities:              
  Increase in accounts receivable     (15,465 )   (41,732 )
  Increase in inventory     (4,434 )   (4,255 )
  Increase in prepaid expenses and other current assets     (57,246 )   (31,412 )
  (Decrease) Increase in accounts payable, accrued liabilities and other payables     (18,479 )   43,036  
   
 
 
    Net cash provided by operating activities     107,315     395,341  
   
 
 
CASH FLOWS FROM INVESTING ACTIVITIES:              
  Purchase of property, plant and equipment     (234,144 )   (325,843 )
  Purchase of intangible assets     (7,872 )   (57,396 )
  Increase in short-term investments     85,304      
  Increase in investments in and advances to affiliates     (10,846 )   (17,173 )
  Purchases of businesses, net of cash acquired     (112,113 )   (301,814 )
   
 
 
    Net cash used in investing activities     (279,671 )   (702,226 )
   
 
 
CASH FLOWS FROM FINANCING ACTIVITIES:              
  Proceeds from notes issue     50,808     400,000  
  Notes issuance cost     (649 )   (3,929 )
  Capital lease obligation principal paid     (6,400 )   (6,982 )
  Proceeds from short-term debt and other payments     23,338     58,144  
  Loan principal paid     (1,800 )   (61,895 )
   
 
 
    Net cash used in financing activities     65,297     385,338  
   
 
 
Effect of exchange rate changes on cash and cash equivalents     (747 )   447  
   
 
 
NET (DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS:     (107,806 )   78,900  
   
 
 
CASH AND CASH EQUIVALENTS, at beginning of period     219,629     34,661  
   
 
 
CASH AND CASH EQUIVALENTS, at end of period   $ 111,823   $ 113,561  
   
 
 

7



SIGNATURES

        Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

    MOBILE TELESYSTEMS OJSC

Date:    October 07, 2003

 

By:

/s/  
VASSILY SIDOROV      
    Name: Vassily Sidorov
    Title: Acting President/CEO



QuickLinks

MTS REVISES ITS FINANCIAL INFORMATION FOR THE SIX MONTHS ENDED JUNE 30, 2003
MOBILE TELESYSTEMS CONDENSED UNAUDITED CONSOLIDATED BALANCE SHEETS AT DECEMBER 31, 2002 AND JUNE 30, 2003
MOBILE TELESYSTEMS CONDENSED UNAUDITED CONSOLIDATED STATEMENTS OF OPERATIONS FOR THE THREE MONTHS ENDED JUNE 30, 2002 AND 2003 AND SIX MONTHS ENDED JUNE 30, 2002 AND 2003
FOR THE SIX MONTHS ENDED JUNE 30 2002 AND JUNE 30, 2003
SIGNATURES