<PAGE>
 
                                                                [EXECUTION COPY]

                               SUPPORT AGREEMENT

                                     among

                           OMOLON GOLD MINING COMPANY

                          CYPRUS AMAX MINERALS COMPANY

                        CYPRUS MAGADAN GOLD CORPORATION

                                 EUROPEAN BANK
                       FOR RECONSTRUCTION AND DEVELOPMENT

                                      and

                    OVERSEAS PRIVATE INVESTMENT CORPORATION






                           Dated as of 30 August 1995
<PAGE>
 

                               SUPPORT AGREEMENT

AGREEMENT dated as of 30 August 1995 among:

     THE CLOSED JOINT STOCK COMPANY "OMOLON GOLD MINING COMPANY", a closed joint
     stock company organized and existing under the laws of the Russian
     Federation (the "Company");

     CYPRUS AMAX MINERALS COMPANY, a corporation organized and existing under
     the laws of the State of Delaware in the United States of America ("Cyprus
     Amax"), and CYPRUS MAGADAN GOLD CORPORATION, a corporation organized and
     existing under the laws of the State of Delaware in the United States of
     America ("Cyprus Magadan" and, together with Cyprus Amax, hereinafter
     referred to as the "U.S. Sponsors"); and

     EUROPEAN BANK FOR RECONSTRUCTION AND DEVELOPMENT ("EBRD") and OVERSEAS
     PRIVATE INVESTMENT CORPORATION ("OPIC" and, together with EBRD, hereinafter
     referred to as the "Project Lenders").

WHEREAS:

(A) Cyprus Amax indirectly owns 100% of the outstanding shares of capital stock
of Cyprus Magadan and Cyprus Magadan owns 50% of the outstanding shares of
capital stock of the Company;

(B) EBRD has entered into a loan agreement dated as of 30 June 1995 (the "EBRD
Loan Agreement") with the Company, pursuant to which EBRD has agreed, subject to
the terms and conditions of the EBRD Loan Agreement, to make a loan to the
Company in an amount not to exceed US$47,500,000;

(C) OPIC has entered into a finance agreement dated as of 30 June 1995 (the
OPIC "Finance Agreement") with the Company, pursuant to which OPIC has agreed,
subject to the terms and conditions of the OPIC Finance Agreement, to make a
loan to the Company in an amount not to exceed US$52,500,000; and

(D) it is a condition precedent to the obligation of EBRD to make disbursements
to the Company under the EBRD Loan Agreement and of OPIC to make disbursements
to the Company under the OPIC Finance Agreement that the U.S. Sponsors enter
into this Agreement.

NOW, THEREFORE, in consideration of EBRD entering into the EBRD Loan Agreement
and OPIC entering into the OPIC Finance Agreement, and in order to

                                       1
<PAGE>
 
induce EBRD to make disbursements under the EBRD Loan Agreement and OPIC to make
disbursements under the OPIC Finance Agreement, the U.S. Sponsors hereby agree
with the Company, EBRD and OPIC as follows:

                            ARTICLE I - DEFINITIONS

Section 1.01. Definitions

     Wherever used in this Agreement or the Schedules hereto, unless the context
otherwise requires, terms defined in the Recitals shall have the meanings
assigned to them in such Recitals, terms defined in the EBRD Loan Agreement
shall have the same meanings in this Agreement and the following terms shall
have the following meanings:

"Company Payment
Amount"                      means an amount which is equal to (a) the aggregate
                             of all payments and withdrawals which contravene
                             the Company Payment Restrictions, and (b) all such
                             other damages, losses, costs and expenses suffered
                             or incurred by the Project Lenders as a result of,
                             or in connection with, any breach of the Company
                             Payment Restrictions.

"Company Payment
Restrictions"               means:

                            (a) the restrictions, under any provision of the
                            Financing Agreements, on the use by the Company or
                            either U.S. Sponsor of the proceeds of the Loan or
                            the OPIC Loan or any other funds of the Company;

                            (b) the restrictions on payments and all other
                            obligations of the Company under Sections 6.01 and
                            6.08(c) of the EBRD Loan Agreement and Sections 6.01
                            and 6.08(c) of the OPIC Finance Agreement; and

                            (c) the restrictions, under the EBRD Loan Agreement,
                            the OPIC Finance Agreement, the Offshore Account
                            Pledge and the Russian Account Pledge, on
                            withdrawals by the Company of funds from the
                            Offshore Bank Account and the subaccounts thereof
                            and from the Russian Bank Accounts and all other
                            obligations of the Company under Sections 5.10,
                            5.11, 5.12, 5.13 and 5.14 of the EBRD Loan Agreement
                            and Sections 5.10, 5.11, 5.12, 5.13 and 5.14 of the
                            OPIC Finance Agreement.
     

                                       2
<PAGE>
 
"Company Security
Restrictions"                means the obligations of the Company under Sections
                             6.03, 6.04 and 6.05 of the EBRD Loan Agreement and
                             under Sections 6.03, 6.04 and 6.05 of the OPIC
                             Finance Agreement.

"Junior Indebtedness"        means any and all of the Company's obligations,
                             whether existing on the date hereof or arising
                             after the date hereof, to make payments of whatever
                             nature to either U.S. Sponsor, including without
                             limitation any and all of the Company's obligations
                             to make payments of principal, interest, management
                             fee and other amounts to either U.S. Sponsor under
                             the Management Agreement or in respect of any loan
                             or other advance of funds by such U.S. Sponsor to
                             the Company, but excluding reimbursements to either
                             U.S. Sponsor for amounts which constitute Operating
                             Costs.

"Senior Indebtedness"        means any and all of the Company's obligations to
                             make payments of principal, interest, fees,
                             charges, commissions, indemnities and other amounts
                             to the Project Lenders under the EBRD Loan
                             Agreement, the OPIC Finance Agreement and the other
                             Financing Agreements.

Section 1.02. Singular/Plural - Persons - References - Headings

(a) In this Agreement, unless the context otherwise requires, words denoting the
singular include the plural and vice versa, and words denoting persons include
corporations, partnerships and other legal persons.

(b) In this Agreement, reference to a specified Article, Section or Schedule
shall be construed as a reference to that specified Article, Section or Schedule
of this Agreement.

(c) The headings and the Table of Contents are inserted for convenience of
reference only and shall not affect the interpretation of this Agreement.

                        ARTICLE II- SUPPORT OBLIGATIONS

Section 2.01. U.S. Sponsors' Support Obligations

(a) Each U.S. Sponsor shall use its best efforts to provide to the Company such
assistance of a personnel, management and technical nature as may be reasonably
required to enable the Company to carry out the Project, provided that the U.S.

                                       3
<PAGE>
 
Sponsors shall be relieved from such obligations to the extent that the Project
Lenders take any action which prevents the U.S. Sponsors from performing such
obligations.

(b) Each U.S. Sponsor shall use its best efforts in its capacity as a direct or
indirect shareholder in the Company to cause the Company at all times to:

       (1) carry out the Project in accordance with the requirements of the EBRD
       Loan Agreement, the OPIC Finance Agreement and the other Financing
       Agreements and in accordance with the Development Plan; and

       (2) maintain in full force and effect all Project Agreements to which the
       Company is a party except as set forth in Section 5.09 of the EBRD Loan
       Agreement and Section 5.09 of the OPIC Finance Agreement.

(c) To the extent that the Company has insufficient funds for such purpose, the
U.S. Sponsors shall jointly and severally provide the Company with sufficient
funds to enable the Company:

       (1) to fulfil its obligations with respect to the Evenskoye Field under
       the terms of the License Agreement; and

       (2) to take such preventive, remedial or other actions as may be
       necessary in connection with any release or threatened release of any
       pollutants or hazardous materials at any site or facility owned, operated
       or leased by the Company (or any predecessor or successor in interest to
       the Company) which was caused by or related to the negligence or wilful
       misconduct of, or any breach of its obligations under any Project
       Agreement by, either U.S. Sponsor.

(d) Each U.S. Sponsor shall perform all of its obligations under the Project
Agreements to which such U.S. Sponsor is a party.

(e) Each U.S. Sponsor agrees that it will not take any action, in its capacity
as a shareholder of the Company or otherwise, which reasonably and foreseeably
would have a Material Adverse Effect.

Section 2.02. Special Obligations of Cyprus Magadan

      Without limiting its obligations under Section 2.01, Cyprus Magadan shall
provide to the Company the personnel, equipment, facilities and other assistance
as provided for in the Management Agreement. Cyprus Magadan shall ensure that
such personnel are qualified and experienced and shall use its best efforts to
cause such personnel to carry out their duties in accordance with the
requirements of the EBRD Loan Agreement, the OPIC Finance Agreement and the
other Financing Agreements, the Management Agreement, all applicable laws and
the Development Plan.

                                       4
<PAGE>
 
Section 2.03. Special Obligations of Cyprus Amax

     Cyprus Amax shall cause Cyprus Magadan to perform all of its obligations
under this Agreement.

Section 2.04. Not a Guaranty

(a) For the avoidance of doubt, the parties hereto acknowledge and confirm that
the obligations of the U.S. Sponsors under Sections 2.01 through 2.03 are not
intended to constitute a guaranty of the payment obligations of the Company
under the EBRD Loan Agreement, the OPIC Finance Agreement and the other
Financing Agreements.

(b) Notwithstanding the foregoing, (1) the U.S. Sponsors shall be liable to the
Project Lenders for any losses, damages, liabilities, costs, expenses and other
amounts suffered or sustained by the Project Lenders arising out of any breach
by either U.S. Sponsor of its obligations under Sections 2.01 through 2.03, and
(2) nothing in this Agreement shall affect the obligations of Cyprus Magadan
under the Cyprus Magadan Guaranty or the obligations of Cyprus Amax under the
Cyprus Amax Guaranty.

                       ARTICLE III- INDEMNITY OBLIGATIONS

Section 3.01. Environmental Liability

(a) The U.S. Sponsors jointly and severally agree, on first written demand from
either Project Lender, to indemnify and hold harmless each Project Lender and
its officers, directors, employees, agents and servants against and from any and
all liabilities, obligations, losses, damages (compensatory, punitive or
otherwise), penalties, claims, actions, taxes, duties, suits, costs and expenses
(including, without limitation, reasonable legal counsel's fees and expenses and
costs of investigation) of whatsoever kind and nature, including, without
prejudice to the generality of the foregoing, those arising in contract or tort
(including, without limitation, negligence) or (subject to (2) below) by strict
liability or otherwise, which are imposed on, incurred by or asserted against
such Project Lender or any of its officers, directors, employees, agents or
servants (whether or not also indemnified by any other person under any other
document) and which in any way relate to or arise out of, whether directly or
indirectly:

       (1) any release or use or threatened release of any pollutants or
       hazardous materials at any site or facility owned, operated or leased by
       the Company (or any predecessor or successor in interest to the Company)
       prior to the Project Completion Date or any other environmental liability
       traceable to an event or condition relating to the Project or the Company
       that occurred or existed prior to the Project Completion Date;

       (2) any release or use or threatened release of any pollutants or
       hazardous materials at any site or facility owned, operated or leased by
       the Company (or

                                       5
<PAGE>
 
       any predecessor or successor in interest to the Company) or any other
       environmental liability traceable to an event or condition relating to
       the Project or the Company, which in either case was caused by or related
       to the negligence or wilful misconduct of, or any breach of its
       obligations under any Project Agreement by, either U.S. Sponsor; or

       (3) any preventive, remedial or other action, including without
       limitation suspension or termination of operations at the Kubaka Field,
       which may be required by the Russian Federation or any political
       subdivision thereof, or any ministry, agency or instrumentality of the
       Russian Federation or any political subdivision thereof, under the
       Environmental Standards and under applicable statutes, laws, regulations,
       rules, orders and decrees as in effect and as interpreted by the relevant
       authorities on the date hereof, in connection with the existing tailings
       pond at the Kubaka Field.

(b) Any claim made by either Project Lender under Section 3.01(a) shall set
forth in reasonable detail the origin and cause of such claim.

(c) The indemnity obligations of the U.S. Sponsors under Section 3.01(a) shall
survive the expiry or termination of this Agreement.

Section 3.02. Breach of Company Payment and Security Restrictions

(a) If the Company at any time breaches one of the Company Payment Restrictions,
the following provisions shall apply:

       (1) If the act or omission of the Company which constituted a breach of
       the Company Payment Restrictions was proposed or submitted to the Board
       of Directors or the shareholders of the Company and the Board of
       Directors or the shareholders of the Company then approved such act or
       omission or failed to take action to prevent such act or omission from
       occurring, then the U.S. Sponsors shall be jointly and severally
       obligated to indemnify the Project Lenders by paying to them on first
       written demand an amount equal to 100% of the Company Payment Amount;
       provided that this Section 3.02(a)(1) shall not apply to any payment of
       dividends which breaches the Company Payment Restrictions if:

              (A) on the date of such payment, the U.S. Sponsors and the Company
              had jointly delivered to the Project Lenders a certificate
              confirming, to the best of their knowledge after due inquiry,
              that, as of the date of such payment, no Event of Default or
              Potential Event of Default had occurred and was continuing; and

              (B) the breach of the Company Payment Restrictions was due solely
              to the existence of a Potential Event of Default which had not
              been notified by either Project Lender to the Company on or prior
              to the date of such payment.

                                       6
<PAGE>
 
       (2) In the case of any breach of the Company Payment Restrictions other
       than one to which Section 3.02(a)(1) applies, the U.S. Sponsors shall be
       jointly and severally obligated to indemnify the Project Lenders by
       paying to them on first written demand an amount equal to the greater of:

              (A) 50% of the Company Payment Amount; and

              (B) the portion of the Company Payment Amount which was received
              by the U.S. Sponsors;

       provided that this Section 3.02(a)(2) shall not apply to any payment of
       dividends which breaches the Company Payment Restrictions if:

                     (i) on the date of such payment, the U.S. Sponsors and the
                     Company had jointly delivered to the Project Lenders a
                     certificate confirming, to the best of their knowledge
                     after due inquiry, that, as of the date of such payment, no
                     Event of Default or Potential Event of Default had occurred
                     and was continuing; and

                     (ii) the breach of the Company Payment Restrictions was due
                     solely to the existence of a Potential Event of Default
                     which had not been notified by either Project Lender to the
                     Company on or prior to the date nine months after the date
                     of such payment.

       (b) If the Company at any time breaches one or more of the Company
       Security Restrictions, and if such breach has not been remedied within 45
       days after receipt of notice of such breach, the following provisions
       shall apply:

              (1) If the act or omission of the Company which constituted a
              breach of the Company Security Restrictions was proposed or
              submitted to the Board of Directors or shareholders of the Company
              and the Board of Directors or shareholders of the Company then
              approved such act or omission or failed to take action to prevent
              such act or omission from occurring, then the U.S. Sponsors shall
              be jointly and severally obligated to indemnify each Project
              Lender by paying to it on first written demand an amount equal to
              100% of all amounts from time to time due and payable by the
              Company to such Project Lender under the Financing Agreements
              which the Company fails to irrevocably discharge within five days
              of the same falling due.

              (2) In the case of any breach of the Company Security Restrictions
              other than that referred to in Section 3.02(b)(1), the U.S.
              Sponsors shall be jointly and severally obligated to indemnify
              each Project Lender by paying to it on first written demand an
              amount equal to 50% of all amounts from time to time due and
              payable by the Company to such Project Lender under the Financing
              Agreements which the Company fails to irrevocably discharge within
              five days of the same falling due.

       (c) For purposes of this Section 3.02, the burden of proof with respect
       to whether an act or omission which is referenced in this Section 3.02
       was proposed or submitted

                                       7
<PAGE>
 
to the Board of Directors or shareholders of the Company shall fall upon the
U.S. Sponsors.

Section 3.03. Transfer to Amax Gold; Expropriatory Action

       If:

       (1) in accordance with Section 5.03(b), Cyprus Amax transfers its shares
       in Cyprus Magadan to Amax Gold and, as a result thereof, the License is
       terminated; or

       (2) any Expropriatory Action (as defined in the Cyprus Magadan Guaranty)
       occurs after the Project Completion Date which:

              (A) was provoked, instigated or caused by or in retaliation for,
              or continued because of any unreasonable or illegal action
              (including, without limitation, any corrupt practice) of either
              U.S. Sponsor;

              (B) was preventable or curable by the exercise of reasonable
              diligence by either U.S. Sponsor; or

              (c) was caused as a result of or attributable to, or continued as
              a consequence of, any agreement, consent or instruction (whether
              express or implied, written or oral) made by either U.S. Sponsor,

then the U.S. Sponsors shall be jointly and severally obligated to indemnify the
Project Lenders by paying to them on first written demand from either Project
Lender an amount equal to the aggregate of the outstanding principal, interest
and other amounts owing under the EBRD Loan Agreement, the OPIC Finance
Agreement and the other Financing Agreements as of the date of such demand
(whether or not such amounts are then due and payable by the Company).

                          ARTICLE IV - SUBORDINATION

Section 4.01. Subordination in Right of Payment

(a) Except as provided in Section 4.01(b), the payment of all or any part of the
Junior Indebtedness shall be postponed and subordinated to the payment in full
of all amounts due and payable in respect of the Senior Indebtedness and no
payments or other distributions whatsoever in respect of any part of the Junior
Indebtedness shall be made nor shall any property or assets of the Company be
applied to the purchase or other acquisition or retirement of any part of the
Junior Indebtedness.

(b) The Company may make payments to the U.S. Sponsors on account of the Junior
Indebtedness so long as no Event of Default or Potential Event of Default has
occurred and is continuing and such payment is otherwise permitted under the
terms

                                       8
<PAGE>
 
of the EBRD Loan Agreement, the OPIC Finance Agreement and the other Financing
Agreements.

Section 4.02. Subordination in Liquidation

     In the event of any dissolution, winding up, liquidation, readjustment,
reorganization or other similar proceedings relating to the Company or to its
creditors, as such, or to its property, of whatever nature:

(a) the Senior Indebtedness shall first be paid in full before either U.S.
Sponsor shall be entitled to receive and to retain any payment or distribution
in respect of the Junior Indebtedness;

b) all payments and distributions of any kind or character in respect of the
Junior Indebtedness to which either U.S. Sponsor would be entitled if the Junior
Indebtedness were not subordinated pursuant to this Agreement shall be made
directly to the Project Lenders;

(c) each U.S. Sponsor shall promptly file a claim or claims, in the form
required in such proceedings, for the full outstanding amount of the Junior
Indebtedness owing to such U.S. Sponsor and shall cause such claim or claims to
be approved and all payments and other distributions in respect thereof to be
made directly to the Project Lenders; and

(d) each U.S. Sponsor hereby irrevocably agrees that each Project Lender may, at
its sole discretion, in the name of such U.S. Sponsor or otherwise, demand, sue
for, collect, receive and give receipt for any and all such payments or
distributions, and file, prove and vote or consent in any such proceedings with
respect to any and all claims of such U.S. Sponsor relating to the Junior
Indebtedness.

Section 4.03. Pledge of Junior Indebtedness

(a) As security for all of the Senior Indebtedness, each U.S. Sponsor hereby
creates a pledge of rights in favor of the Project Lenders over (1) all of such
U.S. Sponsor's rights, title, benefit and interest (present and future) in and
to the Junior Indebtedness, (2) all monies whatsoever payable to or to the
account of such U.S. Sponsor in respect of the Junior Indebtedness, and (3) all
other rights and benefits whatsoever accruing to such U.S. Sponsor in connection
with the Junior Indebtedness.

(b) The pledge created pursuant to Section 4.03(a) shall be without prejudice
and in addition to any other rights which may be held by the Project Lenders or
granted to the Project Lenders by the Company or any other person for or in
respect of the Senior Indebtedness and such pledge shall remain in full force
and effect as continuing security to the Project Lenders until the Senior
Indebtedness has been paid in full. When the Senior Indebtedness has been paid
in full and the Project Lenders are satisfied that no payment received by the
Project Lenders in respect thereof may be avoided or adjusted in bankruptcy or
otherwise, the Project Lenders shall, upon the

                                       9
<PAGE>
 
request of each U.S. Sponsor, issue an absolute and unconditional release of
such pledge.

(c) The Company acknowledges the existence of the pledge of rights in respect of
the Junior Indebtedness created by Section 4.03(a), the value of which on the
date of this Agreement is nil.

Section 4.04. Trust

       In the event that either U.S. Sponsor receives any payment or other
distribution of any kind or character from the Company or from any other source
whatsoever in respect of any part of the Junior Indebtedness, other than as
expressly permitted by the terms of this Agreement, such payment or other
distribution shall be received in trust for the Project Lenders and promptly
turned over by such U.S. Sponsor to the Project Lenders.

Section 4.05. Application of Payments

       All payments and distributions received by the Project Lenders in respect
of the Junior Indebtedness, to the extent received in or converted into cash,
may be applied by the Project Lenders first to the payment of any and all
expenses (including lawyers' fees and legal expenses) paid or incurred by the
Project Lenders in enforcing this Agreement or in endeavoring to collect or
realize upon any part of the Junior in Indebtedness or any security therefor,
and any balance thereof shall, solely as between the U.S. Sponsors and the
Project Lenders, be applied by the Project Lenders, in such order and manner of
application as may be prescribed in the Security Sharing Agreement, toward the
payment of the Senior Indebtedness remaining unpaid; but, as between the Company
and its creditors, no such payments or distributions of any kind or character
shall be deemed to be payments or distributions in respect of the Senior
Indebtedness and, notwithstanding any such payments or distributions received by
the Project Lenders in respect of the Junior Indebtedness and so applied by
the Project Lenders toward the payment of the Senior Indebtedness, the U.S.
Sponsors shall be subrogated to the then existing rights of the Project Lenders,
if any, in respect of the Senior Indebtedness only at such time as this
Agreement shall have been discontinued as provided for in Section 6.04.

Section 4.06. U.S. Sponsors' Affirmative Covenants

    Each U.S. Sponsor shall, from time to time:

(a) promptly notify the Project Lenders of the issuance of any promissory note
or other instrument to evidence the Junior Indebtedness or any part thereof,
upon request by either Project Lender cause any part of the Junior Indebtedness
which is not evidenced by a promissory note or other instrument of the Company
to be so evidenced and cause to be clearly inserted in any promissory note or
other instrument which at any time evidences any part of the Junior Indebtedness
a statement to the

                                       10
<PAGE>
 
effect that the payment thereof is subordinated in accordance with the terms of
this Agreement;

(b)   mark its books and records, and cause the Company to mark its books and
records, so as to clearly indicate that the Junior Indebtedness is subordinated
in accordance with the terms of this Agreement;

(c)   upon request by either Project Lender, and as collateral security for all
Senior Indebtedness, endorse without recourse, deliver and pledge jointly to the
Project Lenders any promissory notes or other instruments evidencing the Junior
Indebtedness and otherwise assign jointly to the Project Lenders the Junior
Indebtedness and any security therefor and guaranties thereof, all in a manner
satisfactory to the Project Lenders; and

(d)   execute such further documents or instruments and take such further action
as either Project Lender may reasonably from time to time request to carry out
the terms of this Agreement.


Section 4.07. U.S. Sponsors' Negative Covenants

      Neither U.S. Sponsor shall, without the prior written consent of both
Project Lenders:

(a)   require or accept, by set-off or otherwise, any prepayment or accelerated
payment or repayment in respect of any part of the Junior Indebtedness, except
as may be required under Section 4.02;

(b)   cancel, waive, forgive, transfer or assign, or attempt to enforce or
collect, any part of the Junior Indebtedness or any rights in respect thereof;

(c)   take any collateral security for any part of the Junior Indebtedness; or

(d)   commence, or join with any other creditor in commencing, any bankruptcy,
reorganization or insolvency proceedings with respect to the Company.


Section 4.08. Waivers by U.S. Sponsors

      Each U.S. Sponsor hereby waives notice of the non-payment of all or any
part of the Senior Indebtedness and all diligence in collection or protection of
or realization upon the Senior Indebtedness or any part thereof or any security
therefor.


Section 4.09. Actions by the Project Lenders

      Each Project Lender may, from time to time, whether before or after any
discontinuance of this Agreement, at its sole discretion and without notice to
either U.S. Sponsor, take any or all of the following actions:

                                       11
<PAGE>
 
(a) retain or obtain a security interest in any property to secure any part of
the Senior Indebtedness;

(b) retain or obtain the primary or secondary obligation of any obligor or
obligors with respect to any part of the Senior Indebtedness;

(c) extend or renew for one or more periods (whether or not longer than the
original period), alter or exchange any part of the Senior Indebtedness, or
release or compromise any obligation of any nature of any obligor with respect
to any part of the Senior Indebtedness; and

(d) release its security interest in, or surrender, release or permit any
substitution or exchange for, all or any part of any property securing any part
of the Senior Indebtedness, or extend or renew for one or more periods (whether
or not longer than the original period) or release, compromise, alter or
exchange any obligations of any nature of any obligor with respect to any such
property.

Section 4.10. Company's Obligations

     The Company agrees to be bound by the terms and provisions of this
Agreement, to make no payments or distributions contrary to the terms and
provisions hereof and to do every other act and thing necessary or appropriate
to carry out such terms and provisions.

            ARTICLE V - REPRESENTATIONS AND WARRANTIES AND COVENANTS
                              OF THE U.S. SPONSORS

Section 5.01. Representations and Warranties

        Each U.S. Sponsor represents and warrants to the Project Lenders that:

(a) it is duly organized and validly existing under the laws of the State of
Delaware in the United States of America and has all requisite power and
authority, corporate or otherwise, to execute, deliver and perform all of its
obligations under this Agreement;

(b) it has taken all necessary action to authorize the execution, delivery and
performance by it of this Agreement;

(c) this Agreement has been duly executed and delivered by it and constitutes
its valid and legally binding obligation, enforceable against it in accordance
with its terms, subject, as to enforceability, to applicable bankruptcy,
insolvency, moratorium and similar laws of general applicability affecting
creditors' rights;

(d) no governmental authorization or action of any kind is or will be necessary
for its valid execution, delivery or performance of this Agreement;

                                       12
<PAGE>
 
(e) the execution, delivery and performance by it of this Agreement do not
require the consent or approval of any of its creditors and will not conflict
with or constitute a breach or default under or violate any provision of its
Charter or any agreement, law, rule, regulation, order, writ, judgment,
injunction, decree, determination or award applicable to it;

(f) there are no actions, proceedings or claims pending or, to the best of its
knowledge, threatened, the adverse determination of which might have a
materially adverse effect on its ability to perform its obligations hereunder or
affect the validity or enforceability hereof;

(g) unless disclosed in writing to the Project Lenders at the time such
statement was made or such information was furnished, no statement made or other
information furnished by it in this Agreement or any other Financing Agreement
to which it is a party in any other document furnished by it or on its behalf
in connection therewith contains any untrue statement of a material fact or
omits to state (as of the date made or furnished) any material fact necessary to
make such statement or information not misleading in light of the circumstances
under which it was made or furnished, provided that, to the extent that any such
statement or information was based upon estimates, forecasts or professional
opinions, such estimates, forecasts or opinions (except as otherwise warranted
herein or therein) were made in good faith and based upon the best available
information, but otherwise it does not warrant that such estimates, forecasts or
opinions will ultimately prove to be correct;

(h) there is no fact known to it that has had, or that could have, a Material
Adverse Effect (other than matters having general applicability and matters of a
general economic, political or legal nature or matters otherwise relating to
general market conditions) that has not been disclosed in writing to the Project
Lenders;

(i) neither it nor any of its officers, directors or authorized employees,
agents or representatives has (1) paid, promised or offered to pay or authorized
the payment of any commission, bribe, pay-off or kickback related to the Project
that violates the U.S. Foreign Corrupt Practices Act of 1977, as amended, (2)
entered into any agreement pursuant to which any such commission, bribe, pay-off
or kickback may or will at any time be paid, or (3) ever been convicted under
the U.S. Foreign Corrupt Practices Act of 1977, as amended, for an offense
related to a project insured or otherwise supported by OPIC;

(j) in the case of Cyprus Amax, it is a corporation created under the laws of
the State of Delaware in the United States of America and is at least 50%
beneficially owned by United States citizens; and

(k) in the case of Cyprus Magadan, it does not own any capital stock or other
form of equity ownership interest in any person other than the Company, it has
no Indebtedness other than Indebtedness under the Cyprus Magadan Guaranty and no
Lien exists with respect to any of its property, revenues or other assets other
than Permitted Liens.

                                       13
<PAGE>
 
Section 5.02. Covenants

     Each U.S. Sponsor covenants and agrees that, unless both Project Lenders
shall otherwise agree in writing:

(a) it shall promptly notify the Project Lenders of any event that constitutes,
or which with the lapse of time or the giving of notice or both would
constitute, an Event of Default and of any other event that has or might have a
materially adverse effect on its ability to perform its obligations hereunder or
on the Project, the Company or the Company's business prospects;

b) it shall permit representatives of the Project Lenders to inspect its 
records pertaining to the Project at any reasonable time;

(c) in the case of Cyprus Magadan, it shall furnish to each of the Project
Lenders, as soon as available but, in any event, within 60 days after the end of
each quarter of each of its fiscal years, two copies of its financial statements
for such quarter prepared in accordance with Generally Accepted Accounting
Principles in the United States and certified by an authorized officer of Cyprus
Magadan;

(d) in the case of Cyprus Amax, it shall furnish to each of the Project
Lenders:

       (1) as soon as available but, in any event, within 60 days after the end
       of each quarter of each of its fiscal years, two copies of its
       consolidated financial statements for such quarter pare in accordance
       with Generally Accepted Accounting Principles in the United States and
       certified by an authorized officer of Cyprus Amax;

       (2) as soon as available but, in any event, within 120 days after the end
       of each of its fiscal years, two copies of its consolidated financial
       statements for such fiscal year prepared in accordance with Generally
       Accepted Accounting Principles in the United States, together with an
       audit report thereon of its independent auditors;

       (3) as soon as available but, in any event, within 60 days after the end
       of each quarter of each of the fiscal years of Amax Gold, two copies of
       the consolidated financial statements for Amax Gold for such quarter
       prepared in accordance with Generally Accepted Accounting Principles in
       the United States and certified by an authorized officer of Amax Gold;
       and

       (4) as soon as available but, in any event, within 120 days after the end
       of each of the fiscal years of Amax Gold, two copies of the consolidated
       financial statements of Amax Gold for such fiscal year prepared in
       accordance with Generally Accepted Accounting Principles in the United
       States, together with an audit report thereon of its independent
       auditors;

(e) it shall furnish to the Project Lenders from time to time such other
information pertaining to the Project or such U.S. Sponsor's financial status as
either Project Lender may reasonably request;

                                       14
<PAGE>
 
(f) in the case of Cyprus Magadan, it shall not (1) engage in any business other
than the holding of shares in the Company, (2) incur any Indebtedness other than
Indebtedness under the Cyprus Magadan Guaranty, or (3) create or permit to exist
any Lien on any of its property, revenues or other assets, present or future,
other than Permitted Liens; and

(g) it shall not, through any of its officers, directors or authorized
shareholders, employees, agents or representatives, pay, promise or offer to pay
or authorize the payment of any commission, bribe, pay-off or kickback related
to the Project that violates the U.S. Foreign Corrupt Practices Act of 1977, as
amended, or enter into any agreement pursuant to which any such commission,
bribe, pay-off or kickback may or will at any time be paid.

Section 5.03. Share Retention

(a) Cyprus Magadan agrees that, until all amounts due or to become due under the
EBRD Loan Agreement, the OPIC Finance Agreement and the other Financing
Agreements have been paid in full, Cyprus Magadan shall not, without the prior
written consent of both Project Lenders, effect any change in its equity
interest in the Company or transfer any of its shares of the capital stock of
the Company. 

(b) Cyprus Amax agrees that, until all amounts due or to become due under the 
EBRD Loan Agreement, the OPIC Finance Agreement and the other Financing
Agreements have been paid in full, Cyprus Amax shall not, without the prior
written consent of both Project Lenders, effect any change in its 100% indirect
shareholding in Cyprus Magadan or permit Cyprus Gold to transfer any of its
shares of the capital stock of Cyprus Magadan other than to another wholly-owned
subsidiary of Cyprus Amax, provided that Cyprus Gold shall, upon 90 days' prior
written notice to the Project Lenders, be entitled to transfer all (but not part
only) of its shares in Cyprus Magadan to Amax Gold if Amax Gold is then an
Affiliate of Cyprus Amax and Amax Gold has agreed in writing to be bound by this
Agreement and to assume all of the obligations of Cyprus Amax under this
Agreement (other than the obligations of Cyprus Amax under this Section 5.03(b))
as if it were originally a party hereto (whereupon Cyprus Amax shall, without
affecting any of its obligations under the Cyprus Amax Guaranty, be released
from its obligations under this Agreement) and not to transfer such shares to
any third party.

(c) Without limiting the foregoing, unless both Project Lenders otherwise agree
in writing, Cyprus Amax shall, until all amounts due or to become due under the
EBRD Loan Agreement, the OPIC Finance Agreement and the other Financing
Agreements have been paid in full:

       (1) indirectly through Cyprus Magadan own at least 50% of the shares in
       the Company at any time outstanding; and

       (2) retain, either directly or indirectly, such control over the
       management of the Company as is provided for in the Company's Charter as
       it exists on the date

                                       15
<PAGE>
 
       hereof and not reduce such management control from that provided for in
       the Company's Charter as it exists on the date hereof.

(d) The U.S. Sponsors acknowledge the difficulty of quantifying losses that may
be suffered by the Project Lenders in the event of a breach by either U.S.
Sponsor of the provisions of Section 5.03(a), 5.03(b) or 5.03(c). Each U.S.
Sponsor therefore agrees that, in the event of any such breach by either U.S.
Sponsor, it shall pay to the Project Lenders, upon first written demand by
either Project Lender, liquidated damages equal to the aggregate of the
outstanding principal, interest and other amounts owing under the EBRD Loan
Agreement, the OPIC Finance Agreement and the other Financing Agreements as of
the date of such demand (whether or not such amounts are then due and payable by
the Company). The U.S. Sponsors agree that such liquidated damages are
reasonable under all circumstances.

                          ARTICLE VI - MISCELLANEOUS

Section 6.01. Notices

      Any notice, request or other communication to be given or made under this
Agreement shall be in writing. Such notice, request or other communication shall
be deemed to have been duly given or made when it shall be delivered by hand,
airmail, telex or facsimile transmission to the party to which it is required or
permitted to be given or made at such party's address specified below its
signature to this Agreement or at such other address as such party shall have
designated by notice to the party giving or making such notice, request or other
communication.

Section 6.02. Rights, Remedies and Waivers

(a) No course of dealing and no delay in exercising, or omission to exercise,
any right, power or remedy accruing to either Project Lender upon any default
under this Agreement or any other agreement shall impair any such right, power
or remedy or be construed to be a waiver thereof or an acquiescence therein; nor
shall the action of either Project Lender in respect of any such default, or any
acquiescence by it therein, affect or impair any right, power or remedy of the
other Project Lender in respect of such default or of either Project Lender in
respect of any other default.

(b) No single or partial exercise of any right, power or remedy accruing to the
Project Lenders upon any default under this Agreement or any other agreement
shall preclude any other or further exercise thereof or the exercise of any
other legal right.

(c) No waiver of any right, power or remedy accruing to the Project Lenders upon
any default under this Agreement or any other agreement shall be effective
unless given in writing by both Project Lenders.

(d) The rights or remedies provided for herein axe cumulative and are not
exclusive of any other rights, powers or remedies provided by law.

                                       16
<PAGE>
 
Section 6.03. Successors and Assigns

     This Agreement shall bind the successors and assigns of each U.S. Sponsor
and shall inure to the benefit of each Project Lender and its successors and
assigns; provided that no U.S. Sponsor may assign any of its obligations
hereunder without the prior written consent of both Project Lenders.

Section 6.04. Term of Agreement

     This Agreement shall continue in force until all monies payable under the
EBRD Loan Agreement, the OPIC Finance Agreement and the other Financing
Agreements shall have been fully and irrevocably paid in accordance with the
provisions thereof. Notwithstanding the foregoing, the provisions of Sections
2.01(c) and 3.01 and this Article VI shall survive any expiry or termination of
this Agreement.

Section 6.05. Governing Law

     This Agreement shall be governed by and construed in accordance with the
laws of the State of New York in the United States of America.

Section 6.06. Jurisdiction

(a) Each U.S. Sponsor hereby irrevocably consents that any legal action or
proceeding against it or any of its properties or assets with respect to any of
its obligations arising under or relating to this Agreement may, at the option
of either Project Lender, be brought in any court of the State of New York or
any Federal court of the United States of America located in the City and State
of New York or in the District of Columbia or the courts of England, as such
Project Lender may elect, and, by execution and delivery of this Agreement, each
U.S. Sponsor hereby submits to and accepts with regard to any such action or
proceeding for itself and in respect of its properties and assets, generally and
unconditionally, the jurisdiction of the aforesaid courts. Each U.S. Sponsor
hereby irrevocably designates, appoints and empowers (1) CT Corporation System,
presently located at 1633 Broadway, New York, New York 10019, U.S.A. as its
agent to receive for and on its behalf service of process in the State of New
York , (2) CT Corporation System, presently located at 1025 Vermont Avenue,
N.W., 4th Floor, Washington, D.C. 20005, U.S.A. as its agent to receive for and
on its behalf service of process in the District of Columbia, and (3) The Law
Debenture Corporation p.l.c., presently located at Princes House, 95 Gresham
Street, London EC2V 7LY, England as its agent to receive for and on its behalf
service of process in England in any legal action or proceeding with respect to
this Agreement. A copy of any such process served on such agent shall be
promptly forwarded by airmail by such Project Lender to such U.S. Sponsor at its
address referred to in Section 6.01, but the failure of such U.S. Sponsor to
receive such copy shall not affect in any way the service of such process as
aforesaid. Each U.S. Sponsor further irrevocably consents to the service of
process in any such action or proceeding by the mailing of copies thereof by
registered or certified airmail, postage

                                       17
<PAGE>
 
prepaid, to such U.S. Sponsor at its address referred to in Section 6.01. The
foregoing, however, shall not limit the fights of the Project Lenders to serve
process in any other manner permitted by law or to bring any legal action or
proceeding or to obtain execution of judgment in any other jurisdiction. Each
U.S. Sponsor further agrees that, to the extent permitted by law, final judgment
against it in any such action or proceeding shall be conclusive and may be
enforced in any other jurisdiction within or outside the United States of
America or England by suit on the judgment, a certified or exemplified copy of
which shall be conclusive evidence of the fact and of the amount of its
indebtedness.

(b) Each U.S. Sponsor hereby irrevocably waives (1) any fight it may have under
the laws of any jurisdiction to a trial by jury in respect of any legal action
or proceeding with respect to this Agreement, (2) any right it may have under
the laws of any jurisdiction (other than New York) to commence by publication
any such legal action or proceeding, (3) any objection which it may now or
hereafter have to the laying of the venue of any such legal action or proceeding
in the State of New York, the District of Columbia or England, and (4) any
claim that the State of New York, the District of Columbia or England is not a
convenient forum for any such legal action or proceeding.

(c) Each U.S. Sponsor hereby (1) irrevocably waives its right to, and agrees not
to request, plead or claim that either Project Lender post, pay or offer, any
cautio judicatum solvi bond, litigation bond or any other bond, fee, payment or 
------ --------- -----
security measure provided by any provision of applicable law as a condition to
commencing or maintaining any such legal action or proceeding, and (2)
irrevocably waives any objection that it may now or hereafter have to the claim
of either Project Lender that such Project Lender should be exempt or immune
from posting, paying, making or offering any such bond, fee, payment or security
measure.

(d) Notwithstanding anything herein to the contrary, no provision of this
Agreement shall be construed as a waiver by EBRD of any of the immunities,
privileges and exemptions granted to EBRD under the Agreement Establishing the
European Bank for Reconstruction and Development and applicable law.

Section 6.07. Counterparts

     This Agreement may be executed in several counterparts, each of which shall
be deemed an original, but all of which together shall constitute one and the
same agreement.

                                       18
<PAGE>
 
IN WITNESS WHEREOF, the parties hereto, acting through their duly authorized
representatives, have caused this Agreement to be signed in their respective
names as of the date first above written.

                                  THE CLOSED JOINT STOCK COMPANY
                                    "OMOLON GOLD MINING COMPANY"

                             By: /s/ Ilya S. Rosenblum
                                 -------------------------------
 [SEAL APPEARS HERE]       Name: Ilya S. Rosenblum
                                 -------------------------------
                          Title: for General Director 
                                 ------------------------------- 
                                 (by Power of Attorney)



                             By: /s/ Ilya S. Rosenblum         
                                 -------------------------------
                           Name: Ilya S. Rosenblum             
                                 -------------------------------
                          Title: for Chief Accountant 
                                 -------------------------------
                                 (by Power of Attorney)
                        Address: Proletariat Street, 14
                                 685000 Magadan
                                 Russian Federation 
                      Attention: General Manager
                          Telex: 145122
                     Answerback: NEGA SU
                            Fax: (1) (907) 887-3000
              
                                    CYPRUS AMAX MINERALS COMPANY
              
                             By: /s/ Farokh S. Hakimi 
                                 -------------------------------
                           Name: Farokh S. Hakimi 
                                 -------------------------------
                          Title: Assistant Treasurer
                                 -------------------------------
                        Address: 9100 East Mineral Circle 
                                 Englewood, Colorado 80112
                                 U.S.A.
                      Attention: General Counsel
                            Fax: (1) (303) 643-5269

                                       19
<PAGE>
 
                                       CYPRUS MAGADAN GOLD CORPORATION

                                   By: /s/ Farokh S. Hakimi
                                       -------------------------------
                                 Name: Farokh S. Hakimi
                                       -------------------------------
                                Title: Assistant Treasurer
                                       -------------------------------  
                              Address: 9100 East Mineral Circle
                                       Englewood, Colorado 80112
                                       U.S.A.
                            Attention: General Counsel
                                  fax: (1) (303) 643-5269

                                                         EUROPEAN BANK 
                                    FOR RECONSTRUCTION AND DEVELOPMENT

                                   By: /s/ Stephane Baverez
                                       -------------------------------
                                 Name: Stephane Baverez 
                                       -------------------------------
                                Title: Principal Banker
                                       ------------------------------- 
                              Address: One Exchange Square
                                       London EC2A 2EH
                                       United Kingdom
                            Attention: Operation Administration Unit
                                Telex: 8812161
                           Answerback: EBRD L G
                                  Fax: (44) (171) 338-6100


                            OVERSEAS AS PRIVATE INVESTMENT CORPORATION


                                   By: /s/ Ronald N. Jonkers
                                       -------------------------------
                                 Name: Ronald N. Jonkers
                                       -------------------------------
                                Title: Assistant General Counsel
                                       ------------------------------- 
                              Address: 1100 New York Avenue, N.W. 
                                       Washington, D.C. 20527 
                                       U.S.A.
                            Attention: Vice President, Finance
                                       (with a separately transmitted copy
                                        to Treasurer)
                                Telex: 4938219
                                  Fax: (1) (202) 408-9859

                                       20
<PAGE>
 
                                                                [EXECUTION COPY]


                   AMENDMENT AGREEMENT TO SUPPORT AGREEMENT


THIS AMENDMENT AGREEMENT is made as of the 28th day of January, 1997 among:

        THE CLOSED JOINT STOCK COMPANY "OMOLON GOLD MINING COMPANY" (the
        "Company");

        CYPRUS AMAX MINERALS COMPANY ("Cyprus Amax") and CYPRUS MAGADAN GOLD
        CORPORATION ("Cyprus Magadan" and, together with Cyprus Amax,
        hereinafter referred to as the "U.S. Sponsors"); and

        EUROPEAN BANK FOR RECONSTRUCTION AND DEVELOPMENT ("EBRD") and OVERSEAS
        PRIVATE INVESTMENT CORPORATION ("OPIC" and, together with EBRD,
        hereinafter referred to as the "Project Lenders").

WHEREAS:

(A) the Company is party to a loan agreement dated as of 30 June 1995, as
amended by an amendment agreement to loan agreement dated as of 7 November 1995
and a second amendment agreement to loan agreement dated as of 22 April 1996
(such loan agreement as so amended, the "EBRD Loan Agreement"), with EBRD,
pursuant to which EBRD has made a loan to the Company in the amount of
US$47,500,000, subject to the terms and conditions of the EBRD Loan Agreement;

(B) the Company is party to a finance agreement dated as of 30 June 1995, as
amended by an amendment agreement to finance agreement dated as of 22 April 1996
(such finance agreement as so amended, the "OPIC Finance Agreement"), with OPIC,
pursuant to which OPIC has made a loan to the Company in the amount of
US$52,500,000, subject to the terms and conditions of the OPIC Finance
Agreement;

(C) in consideration of EBRD entering into the EBRD Loan Agreement and OPIC
entering into the OPIC Finance Agreement and in order to induce EBRD and OPIC to
make disbursements thereunder, the U.S. Sponsors entered into a support
agreement dated as of 30 August 1995 (the "Support Agreement") with the Company
and the Project Lenders;

(D) the Company and EBRD have entered into a third amendment agreement dated as
of 20 November 1996 (the "EBRD Third Amendment Agreement") to the EBRD Loan
Agreement and the Company and OPIC have entered into a second amendment
agreement dated as of 28 January 1997 (the "OPIC Second Amendment Agreement") to
the OPIC Finance Agreement, pursuant to which the maximum principal amounts of
the loans under the EBRD Loan Agreement and the OPIC Finance Agreement are to be
<PAGE>
 
increased US$62,500,000 and US$67,500,000, respectively, subject to the terms
and conditions of the EBRD Third Amendment Agreement and the OPIC Second
Amendment Agreement; and

(E) it is a condition precedent to the effectiveness of the amendments contained
in the EBRD Third Amendment Agreement and the OPIC Second Amendment Agreement
that the U.S Sponsors enter into this Amendment Agreement.

NOW, THEREFORE, the parties hereto agree as follows:

Section 1.    Definitions

     Wherever used in this Amendment Agreement, unless the context shall
otherwise require, the terms defined in the Support Agreement and not separately
defined herein shall have the same meanings when used in this Amendment
Agreement.

Section 2.    Amendments to Support Agreement

(a) Paragraph (B) in the Whereas clause of the Support Agreement is hereby
amended by deleting "a loan agreement dated as of 30 June 1995 (the "EBRD Loan
Agreement")" in the first and second lines and inserting "a loan agreement dated
as of 30 June 1995, as amended by an amendment agreement dated as of 7 November
1995, a second amendment agreement dated as of 22 April 1996 and a third
amendment agreement dated as of 20 November 1996 (such loan agreement as so
amended, the "EBRD Loan Agreement")" in place thereof.

(b) Paragraph (C) in the Whereas clause of the Support Agreement is hereby
amended by deleting "a finance agreement dated as of 30 June 1995 (the "OPIC
Finance Agreement")" in the first and second lines and inserting "a finance
agreement dated as of 30 June 1995, as amended by an amendment agreement dated
as of 22 April 1996 and a second amendment agreement dated as of 28 January 1997
(such finance agreement as so amended, the "OPIC Finance Agreement")" in place
thereof.

(c) Section 2.01 of the Support Agreement is hereby amended by inserting new
subsections (f) and (g) at the end of such Section to read as follows:

       "(f) In the event that either Project Lender determines that the Project
       Costs (including, without limitation, financing costs) necessary to
       achieve physical completion of the Project will, as a result of delays in
       completion or otherwise, exceed the total amount thereof set forth in
       Section 2.01(a) of the EBRD Loan Agreement or Section 2.01(a) of the
       OPIC Finance Agreement, then the U.S. Sponsors shall, within 60 days of
       such determination, be jointly and severally obligated to make cash
       contributions of paid-in capital or Subordinated Shareholder Loans to the
       Company in the full amount of such excess.

       (g) In the event that, prior to registration of the first amendment to
       the Amended and Restated Charter of the Company with the State
       Registration

                                       2
<PAGE>
 
       Chamber and registration of the Company's shares with the Ministry of
       Finance, the Company refunds to any Shareholder or the Ministry of
       Finance confiscates from the Company all or any portion of the paid-in
       capital contributed to the Company by such Shareholder in connection with
       the increase in share capital of the Company pursuant to the first
       amendment to the Amended and Restated Charter of the Company, the U.S.
       Sponsors shall be jointly and severally obligated to make cash
       contributions of Subordinated Shareholder Loans to the Company in the
       full amount of such refund. Until both such registrations take effect,
       Cyprus Magadan shall maintain in its bank account at Pittsburgh National
       Bank in the United States a balance of not less than $6,000,000."

(d)    Section 2.02 of the Support Agreement is hereby amended by numbering the
existing text as sub-section (a) and inserting a new sub-section (b) at the end
of such Section to read as follows:

       "(b) Cyprus Magadan shall, not later than (1) the date on which the
       Company and Cyprus Magadan deliver the Final Completion Certificate
       referred to in Schedule Q to the EBRD Loan Agreement or (2) 15 April
       1997, whichever occurs first, contribute, in a manner satisfactory to
       both Project Lenders, an additional $3,000,000 (or the equivalent thereof
       in other currencies at then current rates of exchange) as paid-in capital
       to the Company either in cash or in kind."

Section 3.    Representations and Warranties

       The Company and each U.S. Sponsor represents and warrants to the Bank as
follows:

(a)    it has all requisite power and authority, corporate or otherwise, to
execute, deliver and perform all of its obligations under this Amendment
Agreement and the Support Agreement as amended by this Amendment Agreement;

(b)    it has taken all necessary action to authorize the execution, delivery
and performance by it of this Amendment Agreement and the Support Agreement as
amended by this Amendment Agreement;

(c)    this Amendment Agreement has been duly executed and delivered by it and
this Amendment Agreement and the Support Agreement as amended by this Amendment
Agreement constitute its valid and legally binding obligations, enforceable
against it in accordance with their respective terms;

(d)    all consents, authorisations and actions of any kind necessary for its
valid execution, delivery and performance of this Amendment Agreement and the
Support Agreement as amended by this Amendment Agreement have been obtained and
are in full force and effect;

(e)    the execution, delivery and performance by it of this Amendment Agreement
and the Support Agreement as amended by this Amendment Agreement do not require
the

                                       3
<PAGE>
 
consent or approval of any of its creditors and will not conflict with or
constitute a breach or default under or violate any provision of its Charter or
any agreement, law, rule, regulation, order, writ, judgement, injunction,
decree, determination or award applicable to it; and

(f)  the representations and warranties made by it in the Support Agreement are
true on and as of the date of this Amendment Agreement with the same effect as
if such representations and warranties had been made on and as of the date of
this Amendment Agreement.

Section 4.    Miscellaneous

(a)  All references to the Support Agreement in the Support Agreement and all
instruments and agreements executed thereunder shall for all purposes refer to
the Support Agreement as amended by this Amendment Agreement. All references to
the EBRD Loan Agreement in the Support Agreement and all instruments and
agreements executed thereunder shall for all purposes refer to the EBRD Loan
Agreement as amended by the EBRD Third Amendment Agreement. All references to
the OPIC Finance Agreement in the Support Agreement and all instruments and
agreements executed thereunder shall for all purposes refer to the OPIC Finance
Agreement as amended by the OPIC Second Amendment Agreement.

(b)  Except to the extent each is expressly amended by the terms of this
Amendment Agreement, all terms and conditions of the Support Agreement and all
other instruments and agreements executed thereunder remain in full force and
effect. This Amendment Agreement may be amended only by an instrument in writing
signed by the Company, the U.S. Sponsors and the Project Lenders.

(c)  This Amendment Agreement may be executed in several counterparts, each of
which shall be deemed an original, but all of which together shall constitute
one and the same agreement.

Section 5.    Governing Law

     This Amendment Agreement shall be governed by and construed in accordance
with the laws of the State of New York in the United States of America.

                                       4
<PAGE>
 
IN WITNESS WHEREOF, the parties hereto have caused this Amendment Agreement to
be executed by their duly authorized representatives as of the day and year
first above written.

                                                  THE CLOSED JOINT STOCK COMPANY
                                                    "OMOLON GOLD MINING COMPANY"

                                        By:  /s/ ILLEGIBLE
                                            ------------------------------------
                                      Name:  
                                            ------------------------------------
                                     Title:
                                            ------------------------------------
[SEAL APPEARS HERE]

                                        By:  /s/ ILLEGIBLE
                                            ------------------------------------
                                      Name:
                                            ------------------------------------
                                     Title:
                                            ------------------------------------


                                        By:  /s/ L.D. Clark
                                            ------------------------------------
                                      Name: L.D. Clark
                                            ------------------------------------
                                     Title:
                                            ------------------------------------


                                                    CYPRUS AMAX MINERALS COMPANY


                                        By: /s/ Farokh S. Hakimi
                                            ------------------------------------
                                      Name: Farokh S. Hakimi
                                            ------------------------------------
                                     Title: Assistant Treasurer
                                            ------------------------------------


                                                 CYPRUS MAGADAN GOLD CORPORATION


                                        By: /s/ Farokh S. Hakimi
                                            ------------------------------------
                                      Name: Farokh S. Hakimi
                                            ------------------------------------
                                     Title: Assistant Treasurer
                                            ------------------------------------


                                         OVERSEAS PRIVATE INVESTMENT CORPORATION


                                        By: /s/ James C. Polan
                                            ------------------------------------
                                      Name: James C. Polan
                                            ------------------------------------
                                     Title: Manager, Project Finance
                                            ------------------------------------

                                       5
<PAGE>
 
                                                                   EUROPEAN BANK
                                              FOR RECONSTRUCTION AND DEVELOPMENT

                                        By:  /s/ Stephane Baverez
                                            ------------------------------------
                                      Name: Stephane Baverez
                                            ------------------------------------
                                     Title: Principal Banker
                                            ------------------------------------

                                            [SEAL APPEARS HERE]

                                       6