Document:

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                                                                    EXHIBIT 10.3

                             STOCK OPTION AGREEMENT

         STOCK OPTION AGREEMENT dated as of May 11, 2001 (this "Agreement")
between Alfa Telecom Limited (as the assignee of Alfa Bank Holdings Limited), a
company incorporated in the British Virgin Islands ("Alfa"), and Global
TeleSystems Europe Holdings B.V. (as the assignee of Global TeleSystems Europe
B.V., which is the assignee of Global TeleSystems, Inc.), a company organized
and registered under the laws of the Netherlands ("GTS").

                              W I T N E S S E T H :

          WHEREAS, Alfa, Capital International Global Emerging Markets Private
Equity Fund, L.P. ("CIG"), Cavendish Nominees Limited ("Cavendish") and First
NIS Regional Fund SICAV ("First Fund") (Cavendish and First Fund together,
"Barings"), as Purchasers, and GTS, as Seller, are parties to a Share Purchase
Agreement (the "Purchase Agreement"), dated April 2, 2001, pursuant to which the
Purchasers agreed to purchase and GTS agreed to sell in the aggregate 12,195,122
of the issued and outstanding shares of Common Stock, par value $.01 per share
("Company Common Stock"), of Golden Telecom, Inc., a Delaware corporation (the
"Company") on the terms and subject to the conditions stated therein;

         WHEREAS, in order to induce Alfa to consummate the transactions
contemplated by the Purchase Agreement, GTS has granted to Alfa the Stock Option
(as hereinafter defined); and

         WHEREAS, in order to induce each of CIG and Barings to enter into the
Purchase Agreement, pursuant to separate stock option agreements of even date
herewith (the "CIG Stock Option Agreement" and the "Barings Stock Option
Agreement", respectively), GTS has granted to each such Person, on the terms and
conditions set forth therein, an irrevocable stock option (the "CIG Stock
Option" and the "Barings Stock Option", respectively; together with the Stock
Option, the "Purchaser Stock Options") to purchase shares of Company Common
Stock Beneficially Owned by GTS;

         NOW, THEREFORE, in consideration of the mutual covenants and agreements
set forth herein and in the Purchase Agreement, and for other good and valuable
consideration, the adequacy of which is hereby acknowledged, the parties hereto
agree as follows:

         SECTION 1. Definitions. Capitalized terms used and not defined herein
have the respective meanings ascribed to them in the Purchase Agreement. In
addition, the following terms have the meanings indicated:

         (a) "Beneficially Own" shall have the meaning assigned to such term in
Rule 13d-3 under the Exchange Act in effect on the date hereof. "Beneficial
Owner" and "Beneficial Ownership" shall have correlative meanings.

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         (b) "Exchange Act" shall mean the Securities Exchange Act of 1934, as
amended, or any successor federal statute as in effect from time to time.

         (c) "Per Share Market Value" means on any particular date (i) the last
sale price per share of the Company Common Stock at the close of business on
such date on the principal stock exchange on which the Company Common Stock has
been listed or, if there is no such price on such date, then the last price on
such exchange on the date nearest preceding such date, or (ii) if the Company
Common Stock is not listed on any stock exchange, the final bid price for a
share of Company Common Stock in the over-the-counter market, as reported by The
Nasdaq Stock Market at the close of business on such date, or the last sales
price if such price is reported and final bid prices are not available, or (iii)
if the Company Common Stock is not quoted on The Nasdaq Stock Market, the bid
price for a share of Company Common Stock in the over-the-counter market as
reported by the National Quotation Bureau Incorporated (or any similar
organization or agency succeeding to its functions of reporting prices), or (iv)
if the Company Common Stock is no longer publicly traded, as determined by an
internationally recognized investment banking firm selected by GTS.

         (d) "Person" shall mean any individual, firm, partnership, association,
group (as such term is defined in Section 13(d)(3) of the Exchange Act, as in
effect on the date hereof), corporation, trust, business trust or other entity,
and includes any successor (by merger or otherwise) of any such entity.

         (e) "Subsidiary" shall mean, with respect to any Person, any other
Person of which at least a majority of the voting power of the voting equity
securities or voting equity interest is owned, directly or indirectly, by such
Person.

         (f) "Trading Day" means (i) a day on which the Company Common Stock is
traded on the principal stock exchange on which the Company Common Stock has
been listed, or (ii) if the Company Common Stock is not listed on any stock
exchange, a day on which the Company Common Stock is quoted in the
over-the-counter market, as reported by The Nasdaq Stock Market, or (iii) if the
Company Common Stock is not quoted on The Nasdaq Stock Market, a day on which
the Company Common Stock is quoted in the over-the-counter market as reported by
the National Quotation Bureau Incorporated (or any similar organization or
agency succeeding to its functions of reporting prices).

         SECTION 2. Grant of Stock Option. GTS hereby grants to Alfa an
irrevocable option (the "Stock Option") to purchase, on the terms and subject to
the conditions hereof, for $11.00 per share (the "Exercise Price") in cash up to
2,000,000 shares (the "Option Shares") of Company Common Stock Beneficially
Owned by GTS. The Exercise Price and number of Option Shares shall be subject to
adjustment as provided in Sections 3(d) or 5 below.

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         SECTION 3. Exercise of Stock Option; Pre-empted Transfers; Compelled
Secondary Offering.

         (a) Alfa or its designee may, subject to the provisions of this Section
3, exercise the Stock Option, in whole or in part, at any time or from time to
time, prior to the Termination Date. "Termination Date" shall mean 10:00 p.m.
London time on the date that is the 60th day from the Closing Date, as such term
is defined in the Purchase Agreement, or such later date as may be specified
pursuant to Section 3(d) below. Notwithstanding the occurrence of the
Termination Date, Alfa shall be entitled to purchase Option Shares pursuant to
any exercise of the Stock Option, on the terms and subject to the conditions
hereof, to the extent Alfa exercised the Stock Option prior to the occurrence of
the Termination Date.

          (b) Alfa may purchase Option Shares pursuant to the Stock Option only
if all of the following conditions are satisfied: (i) no preliminary or
permanent injunction or other order issued by any federal or state court of
competent jurisdiction in the United States shall be in effect prohibiting
delivery of the Option Shares, (ii) any applicable waiting period under the
Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended (the "HSR Act")
shall have expired or been terminated and (iii) any prior notification to or
approval of any other regulatory authority in the U.S. or elsewhere required in
connection with such purchase shall have been made or obtained other than those
which if not made or obtained would not reasonably be expected to result in a
significant detriment to GTS, or to the Company and its Subsidiaries, taken as a
whole or would otherwise prevent the parties from performing, in all material
respects, their obligations hereunder.

         (c) If Alfa shall be entitled to and wishes to exercise the Stock
Option, it or its designee shall do so by giving GTS written notice (the "Stock
Exercise Notice") to such effect, specifying the number of Option Shares to be
purchased and a place and closing date not earlier than five (5) calendar days
nor later than fifteen (15) calendar days from the date of such Stock Exercise
Notice. If the closing cannot be consummated on such date because any condition
to the purchase of Option Shares has not been satisfied or as a result of any
restriction arising under any applicable law or regulation, the closing shall
occur five (5) calendar days (or such earlier time as Alfa or its designee may
specify) after satisfaction of all such conditions and the cessation of all such
restrictions; provided, however, that if the closing has not occurred within 180
calendar days of the giving of the Stock Exercise Notice, then the particular
exercise of the Stock Option shall be deemed to be null and void and the Stock
Option unexercisable as to the Option Shares covered thereby.

         (d) If as of the Termination Date, the sum of (x) the Purchase Price
and (y) the aggregate consideration paid or payable for (1) the number of Option
Shares theretofore purchased by Alfa, plus (2) the aggregate number of shares of
Company Common Stock theretofore purchased by CIG and Barings pursuant to the
CIG Stock Option Agreement and the Barings Stock Option Agreement, respectively,
plus (3) the number of Option Shares covered by any Stock Exercise Notice(s)
theretofore delivered by Alfa or its designees as to which closing on the
related sale and purchase has not occurred other than as a result of default by
Alfa plus (4) the aggregate number of shares of Company Common Stock covered by
an exercise of the CIG Stock Option or the Barings Stock

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Option theretofore delivered by CIG or Barings, respectively or their respective
designees, in each case as to which closing on the related sale and purchase has
not occurred other than as a result of default by CIG or Barings, respectively,
shall equal or exceed $140,000,000, the Termination Date shall automatically be
extended without further act or evidence to the date that is one year from the
Closing Date; provided, however, that with respect to any purchase of Option
Shares pursuant to Stock Exercise Notices delivered after the original
Termination Date, the Exercise Price shall be a price per share equal to the
greater of (i) $11.00 and (ii) the product of (A) 1.2 and (B) the moving average
of the Per Share Market Value of such shares for the sixty (60) Trading Days
immediately preceding (and excluding) the date that Alfa or its designee
delivers the related Stock Exercise Notice (the "Revised Exercise Price"). If
with respect to any shares of Company Common Stock described in subclauses (3)
and (4) of the preceding sentence, the closing shall not have occurred within
the time permitted by Section 3(c) above in the case of the Option Shares and by
Section 3(c) of the CIG Stock Option Agreement and Section 3(c) of the Barings
Stock Option Agreement in the case of the shares described in such subclauses
(3) and (4) and as a result, as of such time the Purchasers in the aggregate
shall have paid GTS less than $140,000,000 in the aggregate for shares of
Company Common Stock purchased and sold pursuant to the Purchase Agreement and
pursuant to exercises of the Purchaser Stock Options, the extension of the
Termination Date shall be deemed rescinded immediately, as of and at such time
and without further act or evidence.

         (e) At any closing pursuant to Section 3(c) or (d) hereof, Alfa or its
designee shall make payment by wire transfer of immediately available funds to
the account or accounts designated by GTS of the aggregate purchase price for
the Option Shares to be purchased and GTS shall deliver to Alfa or its designee
a certificate representing the purchased Option Shares, duly endorsed in blank
for transfer or accompanied by written instruments of transfer in form
satisfactory to the purchaser, duly executed by GTS.

         (f) (i) If the Termination Date shall be extended pursuant to Section
3(d) above, then, if at any time after the original Termination Date, GTS
intends to sell, transfer, write options on or otherwise convey (when used as a
verb, "Transfer" and any sale, transfer, writing of options on or other
conveyance, a "Transfer"), Beneficial Ownership of any shares of Company Common
Stock, then not fewer than thirty (30) calendar days prior to consummating such
Transfer, GTS must provide a written notice of such intention to Alfa, which
notice (the "Notice of Proposed Transfer") will set forth the number of shares
of Company Common Stock that GTS intends to Transfer (the "Transfer Shares").
The Notice of Proposed Transfer shall constitute an offer by GTS, which shall be
irrevocable for a period of fifteen (15) calendar days following receipt of such
notice by Alfa, to permit Alfa or its designee to purchase such shares for cash
at the Revised Exercise Price by delivering a written notice (the "Notice of
Pre-empted Transfer") that Alfa or its designee desires to purchase the Transfer
Shares at such price. Alfa shall have the absolute right to purchase up to 88%
of the number of shares (rounded down to the nearest whole number) identified in
the Notice of Proposed Transfer and a contingent right to purchase the balance
of such shares as provided in the following sentence. In any Notice of
Pre-empted Transfer, Alfa may exercise its contingent purchase right by
indicating that should fewer than all of the balance of the shares set forth in
the Notice of Proposed Transfer be accepted for purchase pursuant to Notices of
Pre-empted Transfer delivered by

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CIG and/or Barings pursuant to Section 3(f)(i) of the CIG Stock Option Agreement
and the Baring Stock Option Agreement, respectively, it desires to purchase some
or all such shares; in which case the number of shares to be purchased and sold
pursuant to Section 3(f)(ii) below shall be adjusted accordingly should CIG
and/or Barings accept for purchase pursuant to Notices of Pre-empted Transfer
fewer than the number of shares allocated for their purchase in the Notices of
Proposed Transfer delivered to them pursuant to Section 3(f)(i) of the CIG Stock
Option Agreement and the Barings Stock Option Agreement, respectively.

         (ii) The consummation of such purchase shall take place on such date,
not later than sixty (60) calendar days after receipt of the Notice of
Pre-empted Transfer by GTS, as Alfa or its designee shall specify. Upon the
consummation of such purchase, (A) GTS shall deliver the certificate or
certificates evidencing the Transfer Shares so purchased duly endorsed in blank
for Transfer or accompanied by written instruments of Transfer in form
satisfactory to the purchaser, duly executed by GTS, free and clear of any
Claims, except for restrictions imposed by the New Shareholders Agreement; and
(B) the purchaser shall simultaneously with the delivery of the certificate or
certificates evidencing the Transfer Shares so purchased pay to GTS the
aggregate Revised Exercise Price of such shares by wire transfer of immediately
available funds to an account or accounts designated by GTS.

         (iii) Alfa shall have no obligation to deliver a Notice of Pre-empted
Transfer in response to any Notice of Proposed Transfer delivered by GTS, and
the decision as to whether to deliver any Notice of Pre-empted Transfer shall be
made by Alfa in the exercise of its sole discretion. In the event that Alfa
shall have received a Notice of Proposed Transfer from GTS but neither Alfa nor
its designee shall have given a Notice of Pre-empted Transfer to GTS with
respect thereto prior to the expiration of the 15-day period following receipt
of such Notice of Proposed Transfer, or in the event that Alfa or its designee
shall have timely given a Notice of Pre-empted Transfer but the purchase and
sale of the subject Transfer Shares shall not have been consummated (through no
fault of GTS) within the applicable 60-day period following delivery of the
Notice of Pre-empted Transfer, as the case may be, then GTS may Transfer any of
the subject Transfer Shares specified in the particular Notice of Proposed
Transfer free of any further obligation hereunder; provided however, if such
Transfer is not consummated within sixty (60) calendar days of the expiration of
the applicable period referred to above, GTS must again comply with the
procedures set forth in this Section 3(f).

         (iv) Notwithstanding anything to the contrary contained in this
Agreement, as of the Termination Date (which shall be the one year anniversary
of the Closing if the Termination Date is extended pursuant to Section 3(d)
above), GTS shall have no obligation to deliver any Notice of Proposed Transfer
under this Section 3(f) and may freely Transfer any shares of Company Common
Stock held by it or its affiliates to a third Person without compliance with the
obligations set forth in this Section 3(f).

         (g) If the Termination Date shall not have been extended pursuant to
Section 3(d), then notwithstanding such fact, until the date that is one year
from the Closing Date, Alfa or its designee

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may deliver a written notice to GTS (a "Contingent Call Notice") specifying a
number of shares of Company Common Stock that Alfa or such designee desires to
purchase from GTS at the Revised Exercise Price. If GTS at the date of its
receipt of a Contingent Call Notice then Beneficially Owns any such shares, then
GTS shall sell, and Alfa or its designee shall purchase, the number of shares of
Company Common Stock covered by such notice (or such fewer number of shares of
Company Common Stock then Beneficially Owned by GTS if GTS shall not then
Beneficially Own at least the number of such shares specified in such notice) in
accordance with the procedures set forth in Sections 3(c) and 3(e); provided
that Alfa or its designee may rescind such notice and terminate its obligation
to purchase any shares of Company Common Stock if the shares of Company Common
Stock available for purchase shall number fewer than 10,000.

         (h) During the period commencing on the date that is six (6) months
after the Closing Date through and including the date that is twelve (12) months
after the Closing Date (the "Compelled Secondary Period"), at any time during
such period Alfa may, by written notice delivered to GTS (the "Compelled Sale
Notice") with a copy to the Company, require GTS to exercise one of its demand
registration rights to facilitate an underwritten public offering of all or any
portion of the shares of Company Common Stock then Beneficially Owned by GTS
pursuant to the Seller Registration Rights Agreement. Alfa shall have the right
to deliver one, and only one, Compelled Sale Notice hereunder. The Compelled
Sale Notice shall set forth the number of shares of Company Common Stock then
Beneficially Owned by GTS that are to be included in the registration; provided,
however, such notice must cover no fewer than 100,000 shares. Promptly upon
receipt of the Compelled Sale Notice, and in any event not later than five (5)
days thereafter, GTS will exercise one of its demand registration rights under
the Seller Registration Rights Agreement and will assist and cooperate with the
Company in causing the related registration statement to be filed with the
Securities and Exchange Commission (the "SEC") and thereafter declared effective
by the SEC at the earliest possible dates; provided, however, that GTS shall not
be required to complete the offering unless the price at which the shares are
sold to the public is at least $15.00 per share. From and after the date hereof
through the end of the Compelled Secondary Period, GTS agrees to retain at least
one of its demand registration rights under the Seller Registration Rights
Agreement.

         (i) Notwithstanding anything to the contrary contained in this
Agreement, after the Termination Date, nothing in this Agreement shall prohibit
or prevent GTS or its affiliates from freely Transferring any Shares held by
them to a third Person.

         SECTION 4. Representations and Warranties of GTS. GTS hereby represents
and warrants to Alfa as follows:

         (a) All of the Option Shares and/or Transfer Shares to be purchased and
sold pursuant to the Stock Option or otherwise pursuant to Section 3 have been
duly authorized, validly issued, fully paid and nonassessable, and shall be
delivered free and clear of all Claims, except for Claims arising under the New
Shareholders Agreement.

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         (b) The Board of Directors of the Company has approved of all
transactions contemplated hereby pursuant to Section 203 of the Delaware General
Corporation Law, and otherwise taken the necessary actions to make inapplicable
any other applicable antitakeover statute or similar statute or regulation, to
the acquisition of the Option Shares and/or the Transfer Shares pursuant to this
Agreement.

         SECTION 5. Adjustment upon Changes in Capitalization or Merger.

         (a) In the event of any change in the outstanding shares of Common
Stock by reason of a stock dividend, stock split, split-up, merger,
consolidation, recapitalization, combination, conversion, exchange of shares,
extraordinary or liquidating dividend or similar transaction which would have
the effect of diluting Alfa's rights hereunder, the type and number of shares or
securities purchasable upon the exercise of the Stock Option or upon delivery of
a Notice of Proposed Transfer or a Contingent Call Notice and the Exercise Price
or Revised Exercise Price, as applicable, shall be adjusted appropriately, and
proper provision will be made in the agreements governing such transaction, so
that Alfa or its designee will receive upon exercise of the Stock Option or upon
purchase of Transfer Shares the number and class of shares or other securities
or property that Alfa or its designee would have received in respect of the
Option Shares or Transfer Shares had the Stock Option been exercised or the
Transfer Shares been purchased immediately prior to such event or the record
date therefor, as applicable.

         (b) Without limiting the foregoing, whenever the number of Option
Shares purchasable upon exercise of the Stock Option or the number of Transfer
Shares purchasable following delivery of a Notice of Proposed Transfer or a
Contingent Call Notice is adjusted as provided in this Section 5, the Exercise
Price or Revised Exercise Price shall be adjusted by multiplying the Exercise
Price or Revised Exercise Price by a fraction, the numerator of which is equal
to the number of Option Shares or Transfer Shares purchasable prior to the
adjustment and the denominator of which is equal to the number of Option Shares
or Transfer Shares purchasable after the adjustment.

         SECTION 6. Further Assurances; Remedies.

         (a) Until the original Termination Date, GTS agrees to maintain, free
and clear of any Claims, except for those arising under the New Shareholders
Agreement, sole Beneficial Ownership of at least 2,000,000 shares of Company
Common Stock.

         (b) GTS agrees not to enter into any agreement, arrangement or
understanding that conflicts with its obligations under this Agreement.

         (c) Upon the terms and subject to the conditions hereof, each of the
parties hereto shall (i) make promptly its respective filings, and thereafter
make any other reasonable submissions, under the HSR Act with respect to the
transactions contemplated by this Agreement, (ii) in the event that prior
notification to or approval of any other regulatory authority in the U.S. or
elsewhere is necessary before the Stock Option may be exercised or Transfer
Shares may be purchased,

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cooperating with the other party or, in the case of Alfa, its designee, in
preparing and processing the required notices or applications in order to permit
Alfa or its designee to exercise the Stock Option and purchase Option Shares
pursuant to such exercise or purchase Transfer Shares following delivery of a
Notice of Proposed Transfer or a Contingent Call Notice, and (iii) use its
reasonable best efforts to take, or cause to be taken, all appropriate action,
and to do, or cause to be done, all things necessary, proper or advisable under
applicable laws and regulations to consummate and make effective the
transactions contemplated by this Agreement.

         (d) The parties agree that Alfa or its designee would be irreparably
damaged if for any reason GTS failed to sell and deliver any of the shares of
Company Common Stock deliverable pursuant to Section 3 hereof (or other
securities or property deliverable pursuant to Section 5 hereof) upon exercise
of the Stock Option or following delivery of a Notice of Proposed Transfer or
Contingent Call Notice, as applicable, or to perform any of its other
obligations under this Agreement, and that Alfa or its designee would not have
an adequate remedy at law for money damages in such event. Accordingly, Alfa or
its designee shall be entitled to specific performance and injunctive and other
equitable relief to enforce the performance of this Agreement by GTS.
Accordingly, if Alfa or its designee should institute an action or proceeding
seeking specific enforcement of the provisions hereof, GTS hereby waives the
claim or defense that Alfa or its designee has an adequate remedy at law and
hereby agrees not to assert in any such action or proceeding the claim or
defense that such a remedy at law exists. GTS further agrees to waive any
requirements for the securing or posting of any bond in connection with
obtaining any such equitable relief. This provision is without prejudice to any
other rights that Alfa or its designee may have against GTS for any failure to
perform its obligations under this Agreement.

         SECTION 7. Miscellaneous.

         (a) Amendments; Entire Agreement. This Agreement may not be modified,
amended, altered or supplemented, except upon the execution and delivery of a
written agreement executed by the parties hereto. This Agreement, together with
the Purchase Agreement (including any exhibits and schedules thereto), the
Confidentiality Agreement, the Purchasers' Ancillary Agreements and the Seller's
Ancillary Agreements, contains the entire agreement between the parties hereto
with respect to the subject matter hereof and supersedes all prior and
contemporaneous agreements and understandings, oral or written, with respect to
such transactions.

         (b) Termination. This Agreement shall terminate on the first-year
anniversary of the Closing Date; provided, however, that the termination of this
Agreement shall not relieve any party from (i) any of their obligations which
accrued pursuant to this Agreement prior to such termination or (ii) any breach
of this Agreement.

         (c) Notices. All notices, requests and other communications to either
party hereunder shall be in writing (including facsimile or similar writing) and
shall be given,

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          if to Alfa, to:

                  Alfa Telecom Limited
                  P.O. Box 3339
                  Geneva Place
                  2nd Floor
                  333 Waterfront Drive
                  Road Town
                  Tortola, British Virgin Islands
                  Facsimile No.:
                  Attn.:  Pavel Nazarian, Director

         with a copy to:

                  Akin, Gump, Strauss, Hauer & Feld L.L.P.
                  Robert S. Strauss Building
                  1333 New Hampshire Avenue N.W.
                  Washington, D.C.  20036
                  Facsimile No.:  (202) 887-4288
                  Attn:  Vladimir Lechtman

         if to GTS, to:

                  Global TeleSystems Europe Holdings B.V.
                  Avioport
                  Evert van de Beekstraat 314
                  1118 CX Schiphol Airpot
                  Netherlands
                  Facsimile No.:  +31 20 800 66 02
                  Attn: General Counsel

         with a copy to:

                  Global TeleSystems, Inc.
                  151 Shaftesbury Avenue
                  London WC2H 8AL
                  United Kingdom
                  Facsimile No.:  +44 (0)20 7655 5437
                  Attn:  General Counsel

         and to:

                  Shearman & Sterling
                  9 Appold Street
                  London EC2A 2AP
                  United Kingdom
                  Fascimile No.:  +44 (0)20 7655 5500
                  Attention:  Alberto Luzarraga

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or to such other address or facsimile number as either party may hereafter
specify for the purpose by notice to the other party hereto. Each such notice,
request or other communication shall be effective (i) if given by facsimile,
when such facsimile is transmitted to the facsimile number specified in this
Section and the appropriate facsimile confirmation is received or (ii) if given
by any other means, when delivered at the address specified in this Section.

         (d) Expenses. Each party hereto shall pay its own expenses incurred in
connection with this Agreement, except as otherwise specifically provided herein
and without limiting anything contained in the Purchase Agreement.

          (e) Severability. If any term, provision, covenant or restriction of
this Agreement is held to be invalid, void or unenforceable, the remainder of
the terms, provisions, covenants and restrictions of this Agreement shall remain
in full force and effect and shall in no way be affected, impaired or
invalidated.

          (f) Governing Law; Jurisdiction. This Agreement shall be governed by
and construed in accordance with the laws of the State of New York without
regard to principles of conflicts of law. Any suit, action or proceeding seeking
to enforce any provision of, or based on any matter arising out of or in
connection with, this Agreement or the transactions contemplated hereby may be
brought in any federal or state court located in the State of New York, County
of New York and each of the parties hereby consents to the jurisdiction of such
courts (and of the appropriate appellate courts therefrom) in any such suit,
action or proceeding and irrevocably waives, to the fullest extent permitted by
law, any objection which it may now or hereafter have to the laying of the venue
of any such suit, action or proceeding in any such court or that any such suit,
action or proceeding which is brought in any such court has been brought in an
inconvenient forum. Process in any such suit, action or proceeding may be served
on any party anywhere in the world, whether within or without the jurisdiction
of any such court. Without limiting the foregoing, each party agrees that
service of process on such party as provided in Section 7(c) hereof shall be
deemed effective service of process on such party.

         (g) Waiver of Jury Trial. EACH OF THE PARTIES HERETO HEREBY IRREVOCABLY
WAIVES ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF
OR RELATED TO THIS AGREEMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY.

         (h) Counterparts. This Agreement may be executed in two or more
counterparts, each of which shall be an original, but all of which together
shall constitute one and the same agreement.

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This Agreement may be executed by facsimile signatures and such signature shall
be deemed binding for all purposes hereof, without delivery of an original
signature being thereafter required.

         (i) Headings. The section headings herein are for convenience only and
shall not affect the construction hereof.

         (j) Assignment. This Agreement shall be binding upon each party hereto
and such party's successors and assigns. This Agreement shall not be assignable
by any party hereto (except as set forth herein), but may be assigned by Alfa or
GTS in whole or in part to any direct or indirect affiliate of such party,
provided that such party shall remain liable for any obligations so assigned.
Furthermore, in any Stock Exercise Notice, Notice of Pre-emptive Transfer or
Contingent Call Notice, Alfa may designate any one or both of the other
Purchasers or any of their respective direct or indirect Subsidiaries or any
other Person as the purchaser of all or any portion of the Option Shares or
Transfer Shares subject to such notice, in which case Alfa shall be released
from any liability with respect to the obligation of the designee(s) to complete
the purchase of such shares, provided such designation was made in good faith.

         (k) Currency. Unless otherwise specified in this Agreement, all
references to currency, monetary values and dollars set forth herein shall mean
United States (U.S.) dollars and all payments hereunder shall be made in United
States dollars.

         (l) Survival. All representations, warranties and covenants contained
herein shall survive the execution and delivery of this Agreement and the
consummation of the transactions contemplated hereby.

                            [signature page follows]

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         IN WITNESS WHEREOF, GTS and Alfa have caused this Agreement to be duly
executed as of the day and year first above written.

                                     ALFA TELECOM LIMITED

                                     By:
                                        ---------------------------------------
                                        Name:
                                            -----------------------------------
                                        Title:
                                             ----------------------------------

                                     Global TeleSystems Europe Holdings B.V.

                                     By:
                                        ---------------------------------------
                                        Name:
                                            -----------------------------------
                                        Title:
                                             ----------------------------------

                                       12<PAGE>   1
                                                                    EXHIBIT 10.4

                             STOCK OPTION AGREEMENT

         STOCK OPTION AGREEMENT dated as of May 11, 2001 (this "Agreement")
between Capital International Global Emerging Markets Private Equity Fund, L.P.,
a Delaware limited partnership ("CIG"), and Global TeleSystems Europe Holdings
B.V. (as the assignee of Global TeleSystems Europe B.V., which is the assignee
of Global TeleSystems, Inc.), a company organized and registered under the laws
of the Netherlands ("GTS").

                              W I T N E S S E T H :

         WHEREAS, CIG, Alfa Telecom Limited (as the assignee of Alfa Bank
Holdings Limited, "Alfa"), Cavendish Nominees Limited ("Cavendish") and First
NIS Regional Fund SICAV ("First Fund") (Cavendish and First Fund together,
"Barings"), as Purchasers, and GTS, as Seller, are parties to a Share Purchase
Agreement (the "Purchase Agreement"), dated April 2, 2001, pursuant to which the
Purchasers agreed to purchase and GTS agreed to sell in the aggregate 12,195,122
of the issued and outstanding shares of Common Stock, par value $.01 per share
("Company Common Stock"), of Golden Telecom, Inc., a Delaware corporation (the
"Company") on the terms and subject to the conditions stated therein;

         WHEREAS, in order to induce CIG to consummate the transactions
contemplated by the Purchase Agreement, GTS has granted to CIG the Stock Option
(as hereinafter defined); and

         WHEREAS, in order to induce each of Alfa and Barings to enter into the
Purchase Agreement, pursuant to separate stock option agreements of even date
herewith (the "Alfa Stock Option Agreement" and the "Barings Stock Option
Agreement", respectively), GTS has granted to each such Person, on the terms and
conditions set forth therein, an irrevocable stock option (the "Alfa Stock
Option" and the "Barings Stock Option", respectively; together with the Stock
Option, the "Purchaser Stock Options") to purchase shares of Company Common
Stock Beneficially Owned by GTS;

         NOW, THEREFORE, in consideration of the mutual covenants and agreements
set forth herein and in the Purchase Agreement, and for other good and valuable
consideration, the adequacy of which is hereby acknowledged, the parties hereto
agree as follows:

         SECTION 1. Definitions. Capitalized terms used and not defined herein
have the respective meanings ascribed to them in the Purchase Agreement. In
addition, the following terms have the meanings indicated:

         (a) "Beneficially Own" shall have the meaning assigned to such term in
Rule 13d-3 under the Exchange Act in effect on the date hereof. "Beneficial
Owner" and "Beneficial Ownership" shall have correlative meanings.

         (b) "Exchange Act" shall mean the Securities Exchange Act of 1934, as
amended, or any successor federal statute as in effect from time to time.

         (c) "Per Share Market Value" means on any particular date (i) the last
sale price per share of the Company Common Stock at the close of business on
such date on the principal stock

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<PAGE>   2

exchange on which the Company Common Stock has been listed or, if there is no
such price on such date, then the last price on such exchange on the date
nearest preceding such date, or (ii) if the Company Common Stock is not listed
on any stock exchange, the final bid price for a share of Company Common Stock
in the over-the-counter market, as reported by The Nasdaq Stock Market at the
close of business on such date, or the last sales price if such price is
reported and final bid prices are not available, or (iii) if the Company Common
Stock is not quoted on The Nasdaq Stock Market, the bid price for a share of
Company Common Stock in the over-the-counter market as reported by the National
Quotation Bureau Incorporated (or any similar organization or agency succeeding
to its functions of reporting prices), or (iv) if the Company Common Stock is no
longer publicly traded, as determined by an internationally recognized
investment banking firm selected by GTS.

         (d) "Person" shall mean any individual, firm, partnership, association,
group (as such term is defined in Section 13(d)(3) of the Exchange Act, as in
effect on the date hereof), corporation, trust, business trust or other entity,
and includes any successor (by merger or otherwise) of any such entity.

         (e) "Subsidiary" shall mean, with respect to any Person, any other
Person of which at least a majority of the voting power of the voting equity
securities or voting equity interest is owned, directly or indirectly, by such
Person.

         (f) "Trading Day" means (i) a day on which the Company Common Stock is
traded on the principal stock exchange on which the Company Common Stock has
been listed, or (ii) if the Company Common Stock is not listed on any stock
exchange, a day on which the Company Common Stock is quoted in the
over-the-counter market, as reported by The Nasdaq Stock Market, or (iii) if the
Company Common Stock is not quoted on The Nasdaq Stock Market, a day on which
the Company Common Stock is quoted in the over-the-counter market as reported by
the National Quotation Bureau Incorporated (or any similar organization or
agency succeeding to its functions of reporting prices).

         SECTION 2. Grant of Stock Option. GTS hereby grants to CIG an
irrevocable option (the "Stock Option") to purchase, on the terms and subject to
the conditions hereof, for $11.00 per share (the "Exercise Price") in cash up to
90,909 shares (the "Option Shares") of Company Common Stock Beneficially Owned
by GTS. The Exercise Price and number of Option Shares shall be subject to
adjustment as provided in Sections 3(d) or 5 below.

         SECTION 3. Exercise of Stock Option; Pre-empted Transfers; Compelled
Secondary Offering.

         (a) CIG or its designee may, subject to the provisions of this Section
3, exercise the Stock Option, in whole or in part, at any time or from time to
time, prior to the Termination Date. "Termination Date" shall mean 10:00 p.m.
London time on the date that is the 60th day from the Closing Date, as such term
is defined in the Purchase Agreement, or such later date as may be specified
pursuant to Section 3(d) below. Notwithstanding the occurrence of the
Termination Date, CIG shall be entitled to purchase Option Shares pursuant to
any exercise of the Stock Option, on the terms and subject to the conditions
hereof, to the extent CIG exercised the Stock Option prior to the occurrence of
the Termination Date.

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<PAGE>   3

          (b) CIG may purchase Option Shares pursuant to the Stock Option only
if all of the following conditions are satisfied: (i) no preliminary or
permanent injunction or other order issued by any federal or state court of
competent jurisdiction in the United States shall be in effect prohibiting
delivery of the Option Shares, (ii) any applicable waiting period under the
Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended (the "HSR Act")
shall have expired or been terminated and (iii) any prior notification to or
approval of any other regulatory authority in the U.S. or elsewhere required in
connection with such purchase shall have been made or obtained other than those
which if not made or obtained would not reasonably be expected to result in a
significant detriment to GTS, or to the Company and its Subsidiaries, taken as a
whole or would otherwise prevent the parties from performing, in all material
respects, their obligations hereunder.

         (c) If CIG shall be entitled to and wishes to exercise the Stock
Option, it or its designee shall do so by giving GTS written notice (the "Stock
Exercise Notice") to such effect, specifying the number of Option Shares to be
purchased and a place and closing date not earlier than five (5) calendar days
nor later than fifteen (15) calendar days from the date of such Stock Exercise
Notice. If the closing cannot be consummated on such date because any condition
to the purchase of Option Shares has not been satisfied or as a result of any
restriction arising under any applicable law or regulation, the closing shall
occur five (5) calendar days (or such earlier time as CIG or its designee may
specify) after satisfaction of all such conditions and the cessation of all such
restrictions; provided, however, that if the closing has not occurred within 180
calendar days of the giving of the Stock Exercise Notice, then the particular
exercise of the Stock Option shall be deemed to be null and void and the Stock
Option unexercisable as to the Option Shares covered thereby.

         (d) If as of the Termination Date, the sum of (x) the Purchase Price
and (y) the aggregate consideration paid or payable for (1) the number of Option
Shares theretofore purchased by CIG, plus (2) the aggregate number of shares of
Company Common Stock theretofore purchased by Alfa and Barings pursuant to the
Alfa Stock Option Agreement and the Barings Stock Option Agreement,
respectively, plus (3) the number of Option Shares covered by any Stock Exercise
Notice(s) theretofore delivered by CIG or its designees as to which closing on
the related sale and purchase has not occurred other than as a result of default
by CIG plus (4) the aggregate number of shares of Company Common Stock covered
by an exercise of the Alfa Stock Option or the Barings Stock Option theretofore
delivered by Alfa or Barings, respectively or their respective designees, in
each case as to which closing on the related sale and purchase has not occurred
other than as a result of default by Alfa or Barings, respectively, shall equal
or exceed $140,000,000, the Termination Date shall automatically be extended
without further act or evidence to the date that is one year from the Closing
Date; provided, however, that with respect to any purchase of Option Shares
pursuant to Stock Exercise Notices delivered after the original Termination
Date, the Exercise Price shall be a price per share equal to the greater of (i)
$11.00 and (ii) the product of (A) 1.2 and (B) the moving average of the Per
Share Market Value of such shares for the sixty (60) Trading Days immediately
preceding (and excluding) the date that CIG or its designee delivers the related
Stock Exercise Notice (the "Revised Exercise Price"). If with respect to any
shares of Company Common Stock described in subclauses (3) and (4) of the
preceding sentence, the closing shall not have occurred within the time
permitted by Section 3(c) above in the case of the Option Shares and by Section
3(c) of the Alfa Stock Option Agreement

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and Section 3(c) of the Barings Stock Option Agreement in the case of the shares
described in such subclauses (3) and (4) and as a result, as of such time the
Purchasers in the aggregate shall have paid GTS less than $140,000,000 in the
aggregate for shares of Company Common Stock purchased and sold pursuant to the
Purchase Agreement and pursuant to exercises of the Purchaser Stock Options, the
extension of the Termination Date shall be deemed rescinded immediately, as of
and at such time and without further act or evidence.

         (e) At any closing pursuant to Section 3(c) or (d) hereof, CIG or its
designee shall make payment by wire transfer of immediately available funds to
the account or accounts designated by GTS of the aggregate purchase price for
the Option Shares to be purchased and GTS shall deliver to CIG or its designee a
certificate representing the purchased Option Shares, duly endorsed in blank for
transfer or accompanied by written instruments of transfer in form satisfactory
to the purchaser, duly executed by GTS.

         (f) (i) If the Termination Date shall be extended pursuant to Section
3(d) above, then, if at any time after the original Termination Date, GTS
intends to sell, transfer, write options on or otherwise convey (when used as a
verb, "Transfer" and any sale, transfer, writing of options on or other
conveyance, a "Transfer"), Beneficial Ownership of any shares of Company Common
Stock, then not fewer than thirty (30) calendar days prior to consummating such
Transfer, GTS must provide a written notice of such intention to CIG, which
notice (the "Notice of Proposed Transfer") will set forth the number of shares
of Company Common Stock that GTS intends to Transfer (the "Transfer Shares").
The Notice of Proposed Transfer shall constitute an offer by GTS, which shall be
irrevocable for a period of fifteen (15) calendar days following receipt of such
notice by CIG, to permit CIG or its designee to purchase such shares for cash at
the Revised Exercise Price by delivering a written notice (the "Notice of
Pre-empted Transfer") that CIG or its designee desires to purchase the Transfer
Shares at such price. CIG shall have the absolute right to purchase up to 4% of
the number of shares (rounded down to the nearest whole number) identified in
the Notice of Proposed Transfer and a contingent right to purchase the balance
of such shares as provided in the following sentence. In any Notice of
Pre-empted Transfer, CIG may exercise its contingent purchase right by
indicating that should fewer than all of the balance of the shares set forth in
the Notice of Proposed Transfer be accepted for purchase pursuant to Notices of
Pre-empted Transfer delivered by Alfa and/or Barings pursuant to Section 3(f)(i)
of the Alfa Stock Option Agreement and the Baring Stock Option Agreement,
respectively, it desires to purchase some or all such shares; in which case the
number of shares to be purchased and sold pursuant to Section 3(f)(ii) below
shall be adjusted accordingly should Alfa and/or Barings accept for purchase
pursuant to Notices of Pre-empted Transfer fewer than the number of shares
allocated for their purchase in the Notices of Proposed Transfer delivered to
them pursuant to Section 3(f)(i) of the Alfa Stock Option Agreement and the
Barings Stock Option Agreement, respectively.

         (ii) The consummation of such purchase shall take place on such date,
not later than sixty (60) calendar days after receipt of the Notice of
Pre-empted Transfer by GTS, as CIG or its designee shall specify. Upon the
consummation of such purchase, (A) GTS shall deliver the certificate or
certificates evidencing the Transfer Shares so purchased duly endorsed in blank
for Transfer or accompanied by written instruments of Transfer in form
satisfactory to the purchaser, duly executed by GTS, free and clear of any
Claims, except for restrictions imposed by the New Shareholders Agreement; and
(B) the purchaser shall simultaneously with the delivery of the

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certificate or certificates evidencing the Transfer Shares so purchased pay to
GTS the aggregate Revised Exercise Price of such shares by wire transfer of
immediately available funds to an account or accounts designated by GTS.

         (iii) CIG shall have no obligation to deliver a Notice of Pre-empted
Transfer in response to any Notice of Proposed Transfer delivered by GTS, and
the decision as to whether to deliver any Notice of Pre-empted Transfer shall be
made by CIG in the exercise of its sole discretion. In the event that CIG shall
have received a Notice of Proposed Transfer from GTS but neither CIG nor its
designee shall have given a Notice of Pre-empted Transfer to GTS with respect
thereto prior to the expiration of the 15-day period following receipt of such
Notice of Proposed Transfer, or in the event that CIG or its designee shall have
timely given a Notice of Pre-empted Transfer but the purchase and sale of the
subject Transfer Shares shall not have been consummated (through no fault of
GTS) within the applicable 60-day period following delivery of the Notice of
Pre-empted Transfer, as the case may be, then GTS may Transfer any of the
subject Transfer Shares specified in the particular Notice of Proposed Transfer
free of any further obligation hereunder; provided however, if such Transfer is
not consummated within sixty (60) calendar days of the expiration of the
applicable period referred to above, GTS must again comply with the procedures
set forth in this Section 3(f).

         (iv) Notwithstanding anything to the contrary contained in this
Agreement, as of the Termination Date (which shall be the one year anniversary
of the Closing if the Termination Date is extended pursuant to Section 3(d)
above), GTS shall have no obligation to deliver any Notice of Proposed Transfer
under this Section 3(f) and may freely Transfer any shares of Company Common
Stock held by it or its affiliates to a third Person without compliance with the
obligations set forth in this Section 3(f).

         (g) Notwithstanding anything to the contrary contained in this
Agreement, after the Termination Date, nothing in this Agreement shall prohibit
or prevent GTS or its affiliates from freely Transferring any Shares held by
them to a third Person.

         SECTION 4. Representations and Warranties of GTS. GTS hereby represents
and warrants to CIG as follows:

         (a) All of the Option Shares and/or Transfer Shares to be purchased and
sold pursuant to the Stock Option or otherwise pursuant to Section 3 have been
duly authorized, validly issued, fully paid and nonassessable, and shall be
delivered free and clear of all Claims, except for Claims arising under the New
Shareholders Agreement.

         (b) The Board of Directors of the Company has approved of all
transactions contemplated hereby pursuant to Section 203 of the Delaware General
Corporation Law, and otherwise taken the necessary actions to make inapplicable
any other applicable antitakeover statute or similar statute or regulation, to
the acquisition of the Option Shares and/or the Transfer Shares pursuant to this
Agreement.

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         SECTION 5. Adjustment upon Changes in Capitalization or Merger.

         (a) In the event of any change in the outstanding shares of Common
Stock by reason of a stock dividend, stock split, split-up, merger,
consolidation, recapitalization, combination, conversion, exchange of shares,
extraordinary or liquidating dividend or similar transaction which would have
the effect of diluting CIG's rights hereunder, the type and number of shares or
securities purchasable upon the exercise of the Stock Option or upon delivery of
a Notice of Proposed Transfer and the Exercise Price or Revised Exercise Price,
as applicable, shall be adjusted appropriately, and proper provision will be
made in the agreements governing such transaction, so that CIG or its designee
will receive upon exercise of the Stock Option or upon purchase of Transfer
Shares the number and class of shares or other securities or property that CIG
or its designee would have received in respect of the Option Shares or Transfer
Shares had the Stock Option been exercised or the Transfer Shares been purchased
immediately prior to such event or the record date therefor, as applicable.

         (b) Without limiting the foregoing, whenever the number of Option
Shares purchasable upon exercise of the Stock Option or the number of Transfer
Shares purchasable following delivery of a Notice of Proposed Transfer is
adjusted as provided in his Section 5, the Exercise Price or Revised Exercise
Price shall be adjusted by multiplying the Exercise Price or Revised Exercise
Price by a fraction, the numerator of which is equal to the number of Option
Shares or Transfer Shares purchasable prior to the adjustment and the
denominator of which is equal to the number of Option Shares or Transfer Shares
purchasable after the adjustment.

         SECTION 6. Further Assurances; Remedies.

         (a) Until the original Termination Date, GTS agrees to maintain, free
and clear of any Claims, except for those arising under the New Shareholders
Agreement, sole Beneficial Ownership of at least 90,909 shares of Company Common
Stock.

         (b) GTS agrees not to enter into any agreement, arrangement or
understanding that conflicts with its obligations under this Agreement.

         (c) Upon the terms and subject to the conditions hereof, each of the
parties hereto shall (i) make promptly its respective filings, and thereafter
make any other reasonable submissions, under the HSR Act with respect to the
transactions contemplated by this Agreement, (ii) in the event that prior
notification to or approval of any other regulatory authority in the U.S. or
elsewhere is necessary before the Stock Option may be exercised or Transfer
Shares may be purchased, cooperating with the other party or, in the case of
CIG, its designee, in preparing and processing the required notices or
applications in order to permit CIG or its designee to exercise the Stock Option
and purchase Option Shares pursuant to such exercise or purchase Transfer Shares
following delivery of a Notice of Proposed Transfer, and (iii) use its
reasonable best efforts to take, or cause to be taken, all appropriate action,
and to do, or cause to be done, all things necessary, proper or advisable under
applicable laws and regulations to consummate and make effective the
transactions contemplated by this Agreement.

         (d) The parties agree that CIG or its designee would be irreparably
damaged if for any reason GTS failed to sell and deliver any of the shares of
Company Common Stock deliverable

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pursuant to Section 3 hereof (or other securities or property deliverable
pursuant to Section 5 hereof) upon exercise of the Stock Option or following
delivery of a Notice of Proposed Transfer, as applicable, or to perform any of
its other obligations under this Agreement, and that CIG or its designee would
not have an adequate remedy at law for money damages in such event. Accordingly,
CIG or its designee shall be entitled to specific performance and injunctive and
other equitable relief to enforce the performance of this Agreement by GTS.
Accordingly, if CIG or its designee should institute an action or proceeding
seeking specific enforcement of the provisions hereof, GTS hereby waives the
claim or defense that CIG or its designee has an adequate remedy at law and
hereby agrees not to assert in any such action or proceeding the claim or
defense that such a remedy at law exists. GTS further agrees to waive any
requirements for the securing or posting of any bond in connection with
obtaining any such equitable relief. This provision is without prejudice to any
other rights that CIG or its designee may have against GTS for any failure to
perform its obligations under this Agreement.

         SECTION 7. Miscellaneous.

         (a) Amendments; Entire Agreement. This Agreement may not be modified,
amended, altered or supplemented, except upon the execution and delivery of a
written agreement executed by the parties hereto. This Agreement, together with
the Purchase Agreement (including any exhibits and schedules thereto), the
Confidentiality Agreement, the Purchasers' Ancillary Agreements and the Seller's
Ancillary Agreements, contains the entire agreement between the parties hereto
with respect to the subject matter hereof and supersedes all prior and
contemporaneous agreements and understandings, oral or written, with respect to
such transactions.

         (b) Termination. This Agreement shall terminate on the first-year
anniversary of the Closing Date; provided, however, that the termination of this
Agreement shall not relieve any party from (i) any of their obligations which
accrued pursuant to this Agreement prior to such termination or (ii) any breach
of this Agreement.

         (c) Notices. All notices, requests and other communications to either
party hereunder shall be in writing (including facsimile or similar writing) and
shall be given,

         if to CIG, to:

                  Capital International Global Emerging Markets Private Equity
                    Fund, L.P.
                  135 South State College Boulevard
                  Brea CA 90071-1447
                  Facsimile No.: +1 (714) 671 - 7080
                  Attn.:  Jim Brown

         with a copy to:

                  Capital International Limited
                  25 Bedford Street
                  London WC2E 9HN
                  Facsimile No.: +44 (20) 7864 - 5768
                  Attn:  Ida Levine

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<PAGE>   8

                  - and -

                  Capital Research International Inc.
                  25 Bedford Street
                  London WC2E 9HN
                  Facsimile No.: +44 (20) 7864 - 5814
                  Attn:  Ashley Dunster

         - and to -

                  Fried, Frank, Harris, Shriver & Jacobson
                  99 City Road
                  London EC1Y 1AX
                  Facsimile No.: +44 (20) 7972 - 9602
                  Attn:  Karen Wiedemann

         if to GTS, to:

                  Global TeleSystems Europe Holdings B.V.
                  Avioport
                  Evert van de Beekstraat 314
                  1118 CX Schiphol Airpot
                  Netherlands
                  Facsimile No.:  +31 20 800 66 02
                  Attn: General Counsel

         with a copy to:

                  Global TeleSystems, Inc.
                  151 Shaftesbury Avenue
                  London WC2H 8AL
                  United Kingdom
                  Facsimile No.:  +44 (0)20 7655 5437
                  Attn:  General Counsel

         - and to -

                  Shearman & Sterling
                  9 Appold Street
                  London EC2A 2AP
                  United Kingdom
                  Facsimile No.:  +44 (0)20 7655 5500
                  Attention:  Alberto Luzarraga

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or to such other address or facsimile number as either party may hereafter
specify for the purpose by notice to the other party hereto. Each such notice,
request or other communication shall be effective (i) if given by facsimile,
when such facsimile is transmitted to the facsimile number specified in this
Section and the appropriate facsimile confirmation is received or (ii) if given
by any other means, when delivered at the address specified in this Section.

         (d) Expenses. Each party hereto shall pay its own expenses incurred in
connection with this Agreement, except as otherwise specifically provided herein
and without limiting anything contained in the Purchase Agreement.

          (e) Severability. If any term, provision, covenant or restriction of
this Agreement is held to be invalid, void or unenforceable, the remainder of
the terms, provisions, covenants and restrictions of this Agreement shall remain
in full force and effect and shall in no way be affected, impaired or
invalidated.

          (f) Governing Law; Jurisdiction. This Agreement shall be governed by
and construed in accordance with the laws of the State of New York without
regard to principles of conflicts of law. Any suit, action or proceeding seeking
to enforce any provision of, or based on any matter arising out of or in
connection with, this Agreement or the transactions contemplated hereby may be
brought in any federal or state court located in the State of New York, County
of New York and each of the parties hereby consents to the jurisdiction of such
courts (and of the appropriate appellate courts therefrom) in any such suit,
action or proceeding and irrevocably waives, to the fullest extent permitted by
law, any objection which it may now or hereafter have to the laying of the venue
of any such suit, action or proceeding in any such court or that any such suit,
action or proceeding which is brought in any such court has been brought in an
inconvenient forum. Process in any such suit, action or proceeding may be served
on any party anywhere in the world, whether within or without the jurisdiction
of any such court. Without limiting the foregoing, each party agrees that
service of process on such party as provided in Section 7(c) hereof shall be
deemed effective service of process on such party.

         (g) Waiver of Jury Trial. EACH OF THE PARTIES HERETO HEREBY IRREVOCABLY
WAIVES ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF
OR RELATED TO THIS AGREEMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY.

         (h) Counterparts. This Agreement may be executed in two or more
counterparts, each of which shall be an original, but all of which together
shall constitute one and the same agreement. This Agreement may be executed by
facsimile signatures and such signature shall be deemed binding for all purposes
hereof, without delivery of an original signature being thereafter required.

         (i) Headings. The section headings herein are for convenience only and
shall not affect the construction hereof.

         (j) Assignment. This Agreement shall be binding upon each party hereto
and such party's successors and assigns. This Agreement shall not be assignable
by any party hereto (except as set forth herein), but may be assigned by CIG or
GTS in whole or in part to any direct or indirect

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<PAGE>   10

affiliate of such party, provided that such party shall remain liable for any
obligations so assigned. Furthermore, in any Stock Exercise Notice or Notice of
Pre-emptive Transfer, CIG may designate any one or both of the other Purchasers
or any of their respective direct or indirect Subsidiaries or any other Person
as the purchaser of all or any portion of the Option Shares or Transfer Shares
subject to such notice, in which case CIG shall be released from any liability
with respect to the obligation of the designee(s) to complete the purchase of
such shares, provided such designation was made in good faith.

         (k) Currency. Unless otherwise specified in this Agreement, all
references to currency, monetary values and dollars set forth herein shall mean
United States (U.S.) dollars and all payments hereunder shall be made in United
States dollars.

         (l) Survival. All representations, warranties and covenants contained
herein shall survive the execution and delivery of this Agreement and the
consummation of the transactions contemplated hereby.

                            [signature page follows]

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         IN WITNESS WHEREOF, GTS and CIG have caused this Agreement to be duly
executed as of the day and year first above written.

                                  CAPITAL INTERNATIONAL GLOBAL EMERGING
                                  MARKETS PRIVATE EQUITY FUND, L.P.,
                                  by Capital International Inc., General Partner

                                  By:
                                    --------------------------------------------
                                    Name:
                                        ----------------------------------------
                                    Title:
                                         ---------------------------------------

                                  Global TeleSystems Europe Holdings B.V.

                                  By:
                                    --------------------------------------------
                                    Name:
                                        ----------------------------------------
                                    Title:
                                         ---------------------------------------

                                       11

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