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                                                                   EXHIBIT 10.21

                     AGREEMENT FOR THE SALE AND PURCHASE OF
             SHARES IN GREAT PLAINS PETROLEUM (CYPRUS) LIMITED AND
                       GLOBAL PETROLEUM (CYPRUS) LIMITED

                                    BETWEEN

                     KUBAN PETROLEUM LTD. (BVI) ("SELLER")

                     AND IVANHOE ENERGY INC. ("GUARANTOR")

                                      AND

                 STESANA ENTERPRISES LIMITED (CYPRUS) ("BUYER")

                              Dated 10 August 2000

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THIS AGREEMENT is made on AUGUST 10, 2000.

BETWEEN:

     (1)   Kuban Petroleum Ltd., a company organized and existing under the laws
           of the British Virgin Islands whose registered office is at Columbus
           Center Building, Wickhams Cay, Tortola, British Virgin Islands (the
           "SELLER"); and

     (2)   Stesana Enterprises Limited, a company organized and existing under
           the laws of Cyprus, whose registered office is at 16 Princ. Zenas De
           Tyras St., Karantoki Building, 3rd floor, flat 3, 1065 Nicosia,
           Cyprus (the "BUYER");

     (3)   Ivanhoe Energy Inc., a company organized and existing under the laws
           of Canada with its registered office at Suite 300, 204 Black Street,
           Whitehorse, Yukon Y1A 2M9 ("GUARANTOR");

The Seller and the Buyer the Guarantor shall be collectively referred to as the
"PARTIES" and each individually as the "PARTY".

WHEREAS:

     (A)   The Seller is an indirectly controlled subsidiary of the Guarantor.

     (B)   The Seller beneficially owns one hundred percent (100%) of the shares
           of each of the following legal entities (the "SHARES"):

           Great Plains Petroleum (Cyprus) Limited. ("GREAT PLAINS"), a Cyprus
           limited liability company with its registered office at Chanteclair
           Building, 2 Sofouli Street, Office 205, 1096 Nicosia, Cyprus; and

           Global Petroleum (Cyprus) Limited ("GLOBAL"), a Cyprus limited
           liability company with its registered office at Chanteclair Building,
           Second Floor, 2 Sofouli Street, 1096 Nicosia, Cyprus (hereinafter
           collectively referred to with Great Plains as the "COMPANIES" or each
           the "COMPANY" as the case may be).

     (C)   Great Plains owns fifty percent (50%) of the shares of ZAO Tura
           Petroleum Company (the "TURA SHARES"), a Russian closed joint stock
           company with its registered office at Ulitsa Lenina 67, Tyumen
           625000, the Russian Federation ("TURA"). TNG has contested the
           validity of formation of Tura and hence of Great Plains' rights as a
           shareholder. Tura is currently in bankruptcy proceedings in Tyumen.

     (D)   Pursuant to the Loan Agreement No. 13/l between Great Plains and Tura
           dated 28 January 2000, as amended, (the "TURA LOAN AGREEMENT"), Great
           Plains granted a loan to Tura in the amount of US $ 12,270,000
           (twelve million two hundred seventy thousand US Dollars). As of the
           date of this Agreement, TNG contests the validity of the Tura Loan
           Agreement, and any reference to the Tura Loan Agreement hereunder
           shall not mean and shall not be construed as any warranty, guarantee
           or representation by the Seller and/or the Guarantor to the Buyer
           and/or Buyer's Group with respect to any and all issues related to
           and/or arising from the Tura Loan Agreement. The total amount owed by
           Tura to Great Plains under the Tura Loan Agreement, including
           principal and all interest accrued on it and any other amounts
           payable thereunder as of July 31, 2000, constitute US $14,273,205.

     (E)   Global owns fifty percent (50%) of the shares of ZAO Radonezh
           Petroleum (the "RADONEZH SHARES"), a Russian closed joint stock
           company with its principal office at 55, Respubliki Street, Tyumen,
           625640, Russian Federation ("RADONEZH"). The Tura Shares and the
           Radonezh Shares are collectively referred to as the "RUSSIAN SHARES";
           Tura and Radonezh are collectively referred to as the "RUSSIAN
           COMPANIES".

     (F)   In June 1999, Great Plains initiated arbitral proceedings in
           Stockholm, Sweden against Joint Stock Company Tyumenneftegaz, a
           company organized and existing under the laws of the Russian
           Federation, ("TNG")under the UNCITRAL Arbitration Rules (the
           "PROCEEDINGS"). The

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           Proceedings involve certain claims asserted by Great Plains in
           connection with certain alleged violations of the charter of Tura by
           TNG (the "ASSERTED CLAIMS"). TNG opposes the Proceedings on
           jurisdictional grounds and the hearings on the matter of jurisdiction
           are scheduled in Stockholm on 27-28 September, 2000.

     (G)   It is a condition for the Buyer entering into this Agreement that,
           inter alia, the Guarantor, as a company indirectly controlling the
           Seller, becomes a party to this Agreement as Guarantor to provide the
           guarantee the scope of which is established in Clause 7.1. herein
           below. The Guarantor recognizes the benefit to it of this Agreement
           and the transaction contemplated hereunder.

     (H)   The Parties have agreed on detailed terms and conditions for such
           purchase and sale, as set forth in this Agreement

NOW, THEREFORE, THE PARTIES AGREE as follows:

1.   INTERPRETATION

     1.1 In this Agreement:

"AFFILIATE"                  means, in respect of any person, a "connected
                             person" within the meaning of Section 839 of the
                             Income and Corporation Taxes Act 1988 or an
                             "associated company" within the meaning of Section
                             416 of that Act, as of the date of Closing.

"BUYER'S GROUP"              means the Buyer and any Affiliate of the Buyer,
                             including the Group as of the date of Closing;

"CLOSING"                    means completion of the sale and purchase of the
                             Shares in accordance with this Agreement, as
                             described in Clause 3 herein below;

"COMPANIES' LIABILITIES"     means all liabilities (actual or contingent) of the
                             Companies which currently exist or which arise from
                             any event, act, transaction or omission occurring
                             on or before Closing, except (a) any liabilities
                             that were, are or may be attributable to the
                             actions or omissions of the Russian Companies that
                             were, are, or may be imputed to either of the
                             Companies or any member of the Seller's Group by
                             parties other than the Buyer's Group because of the
                             status of such member of the Seller's Group as a
                             direct or indirect shareholder of, or its ability
                             to directly or indirectly control, either of the
                             Russian Companies, and (b) any tax liabilities of
                             the Buyer's Group arising from or in connection
                             with any and all of the Companies' Liabilities that
                             are deemed assigned to the Buyer and/or the Buyer's
                             Group;

"ENCUMBRANCE"                means a mortgage, charge, pledge, lien, option,
                             restriction, right of first refusal, right of
                             preemption, third-party right or interest, other
                             encumbrance or security interest in the Shares of
                             any kind, or another type of preferential
                             arrangement therein (including, without limitation,
                             a title transfer or retention arrangement) having
                             similar effect;

"GROUP"                      means the Companies and the Russian Companies and a
                             reference to a member of them means any of them.

"SELLER'S GROUP"             means the Seller, the Guarantor and any Affiliate
                             of the Seller or Guarantor as of the date of
                             Closing.

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"WARRANTY"                   means the representations and warranties contained
                             in schedule 3 and any other representation and
                             warranty made herein by or on behalf of the Parties
                             to this Agreement.

1.2 In this Agreement, a reference to:

     (a)   a statutory provision includes a reference to the statutory provision
           as modified or re-enacted or both from time to time before the date
           of this Agreement and any subordinate legislation made under the
           statutory provision before the date of this Agreement;

     (b)   a person includes a reference to any individual, firm, company, body
           corporate, association or partnership, government, state or agency of
           a state, local or municipal authority (whether or not having separate
           legal authority); and

     (c)   a person includes a reference to that person's legal representatives
           and successors; and

     (d)   a clause, paragraph or schedule, unless the context otherwise
           requires, is a reference to a clause or paragraph of or schedule to
           this Agreement;

     (e)   any reference to any English legal term for any action, remedy,
           method of judicial proceeding, legal document, legal status, court,
           officia1 or any legal concept or thing shall, in respect of a
           jurisdiction other than England, be deemed to include what most
           nearly approximates in that jurisdiction to the English legal term;

     (f)   references to any statute or statutory provision are to be construed
           as references to the same as it may have been, or may from time to
           time be, amended, modified or re-enacted, and include references to
           all statutory instruments, orders and regulations for the time being
           made thereunder or deriving validity therefrom;

     (g)   the single includes the plural and vice versa; and

     (h)   All Warranties, representations and obligations in this Agreement
           expressed to be given or entered into by both the Seller and the
           Guarantor are given or entered into by them jointly and severally.
           The Buyer may release or compromise the liability of any of the
           Seller or the Guarantor hereunder without affecting the liability of
           the other. If any liability of any of the Guarantor or the Seller is,
           or becomes, illegal, invalid or unenforceable in any respect, this
           shall not affect or impair the liability to the other under this
           Agreement.

1.3 The headings in this Agreement do not affect its interpretation.

2.  SALE AND PURCHASE

2.1 Seller shall sell or procure the sale with full title guarantee and Buyer
shall buy the Shares and each right accruing or attaching to the Shares (now or
at any time hereafter), and the accounts receivable due from the Companies to
the Seller and/or Ivanhoe shall- be deemed assigned and released as set forth in
Section 6, and such Shares shall be free of any Encumbrance.

2.2 The covenants implied by Section 6(2) and the exclusion of "charges,
encumbrances or rights which that person could not reasonably be expected to
know about" in Section 3(l) of the Law of Property (Miscellaneous Provisions)
Act 1994 shall not apply between the Parties.

2.3 The Seller waives all rights of pre-emption over any of the Shares conferred
on it by the articles of association of each of the Companies.

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2.4 The price for the purchase of the Shares and the accounts receivable deemed
assigned as set forth in Section 6 hereof is twenty nine million twenty-two
thousand nine hundred ninety eight United States Dollars USD 29,022,998 the
"PURCHASE PRICE" representing:

USD 2,250,000 (two million two hundred and fifty thousand U.S. Dollars) for the
Global Petroleum Shares, and

USD 26,772,998 (twenty six million seven hundred seventy two thousand nine
hundred ninety eight U.S. Dollars) for the Great Plains Shares.

3.  CLOSING

3.1 Closing shall occur on the execution and delivery of this Agreement and the
documents set forth in Schedule 2 and shall take place at the office of the law
firm of Tassos Papadopoulos & Co at 2, Sofouli Street, Chanteclair Building, the
second floor, 1096, Nicosia, Cyprus on August 10, 2000, at 9 am.

3.2 At Closing, Seller shall sell, transfer or cause such transfer and assign
(or cause the assignment) all right, title and interest in the Shares and in to
the Buyer, on the terms and conditions set forth in this Agreement, so that upon
Closing, Buyer shall have full and exclusive legal and beneficial right, title
and interest in the Shares. For this purpose, the Parties shall execute and
deliver to each other at the time of execution of this Agreement, the relevant
documents and instruments specified in Schedule 2 hereto.

3.3 The Seller shall ensure that prior to Closing the directors of each of the
Companies hold a meeting of the board of directors of each of the Companies (the
"BOARD MEETINGS") at which the directors, with respect to either Great Plains or
Global as appropriate:

     (a)   vote in favor of the registration of the Buyer as beneficial and
           legal owner of the Shares (subject to the execution at the Closing of
           the instruments of transfer of the Shares signed by the legal owners
           of the Shares and execution at the Closing of Instruments of
           Cancellation terminating the Instruments of Trust with respect to the
           Companies dated 16 April 1997 and 2 April 1996 for Global and Great
           Plains, respectively between the Seller and the registered (legal)
           owners of the Shares, and presentation at the Closing of a duly
           issued authorization of the Central Bank of Cyprus with respect to
           the change in beneficial ownership of the Shares to the Buyer;

     (b)   appoint persons nominated by the Buyer as directors, secretary with
           effect from the end of Closing;

3.4 and procure that at Closing the Companies' Liabilities shall be assumed and
released as provided in clause 6.

3.5 At Closing the Buyer shall pay to the Seller the total price of the Shares
stated in clause 2.4 by an unconditional irrevocable bank transfer order duly
signed and sealed by the Buyer and handed to the officer of the Bank of Cyprus
who shall be present at the Closing (the "OFFICER"). The Buyer, immediately upon
execution of the documents listed in Schedule 2 hereto shall cause the Officer
to debit the Buyer's bank account with the Bank of Cyprus for the full amount of
the Purchase Price and credit the respective Purchase Price, net of any bank
transfer charges, fees, withholding and other payments that may be due
simultaneously with debiting the Buyer's account, to the Seller Trustee's bank
account opened with the Bank of Cyprus. The Seller's Trustee shall be Kuban
Petroleum (Cyprus) Limited, with its registered address at 2, Sofouli Street,
Chanteclair Building, 1096, Nicosia, Cyprus and its bank account with the Bank
of Cyprus, International Business Unit 2-4 Them Dervi Street P.O. Box CY 1599
Nicosia, Cyprus (the "TRUSTEE"). The Buyer shall cause the Officer to issue to
the Seller a credit notice evidencing payment of the full Purchase Price into
the Trustee's account with the Bank of Cyprus. The respective credit advice
shall be certified by the Officer. Immediately upon execution of the documents
listed in Schedule 2 hereto, the Parties shall deliver such documents to Tassos
Papadopoulos & Co (the "ESCROW AGENT"). The Escrow Agent shall hold and release
the documents pursuant to the terms of the

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Escrow Mandate. Upon such release the Closing and the purchase and sale
hereunder shall be deemed completed.

3.6 At Closing the Buyer, the Guarantor and the Seller shall deliver to each
other the documents listed in Schedule 2 hereto.

4.  WARRANTIES

4.1 Each of the Guarantor and Seller warrant to the Buyer, and Buyer warrants to
the Seller, that each of the Warranties made by it is true, accurate, complete
and not misleading at the date of Closing. For this purpose only, where in a
Warranty there is an express or implied reference to the "date of this
Agreement", that reference is to be construed as a reference to the "date of
Closing".

4.2 Each of the Parties acknowledges that the other Party is entering into this
Agreement in reliance on each Warranty which has also been given as a
representation and with the intention of inducing the other Party to enter into
this Agreement.

4.3 Each of the Warranties shall be construed as a separate and independent
warranty and shall be limited and restricted by reference to the terms of each
respective Warranty and the Warranties shall survive Closing.

4.4. The rights and benefits of or under the Warranties may be assigned
(together with any cause of action arising in connection with any Warranty) by
the Parties to their successors in title or to any member of their respective
Group.

5.  ANNOUNCEMENTS

5.1 The Parties shall sign at the time of Closing a pre-agreed text of a joint
Press Release. Save for such Press Release, the Parties agree that the terms and
conditions of this Agreement and any and all other information relating to the
transactions contemplated hereby shall remain confidential for a period of
twelve (12) months, except as required by law and/or stock exchange rules.
During this period such information shall not be disclosed by either Party to
any third party, including but not limited to subsidiaries, affiliates,
officers, directors, and employees of such entities, or any unauthorized person
without the prior written consent of Ivanhoe or Stesana respectively, which
consent shall not be unreasonably withheld, unless and to the extent such
disclosure is required for a proper fulfillment of the Parties' obligations
arising out of this Agreement or if such information is already publicly known
or if a Party or the Parties are legally obliged to disclose such information.

6.  COMPANIES LIABILITIES

6.1 Any and all of the Companies' Liabilities that appear on Schedule 4
vis-a-vis any parties other than the Seller and the Seller's Group upon Closing
shall be assumed by the Seller and/or the Guarantor, and the Companies shall be
fully released of such liabilities. For the consideration paid hereunder, upon
Closing any and all of the Companies' Liabilities due from the Companies to the
Seller and/or Ivanhoe, as reflected on Schedule 4, shall be deemed assigned
accordingly by the Seller and/or Ivanhoe to the Buyer and/or to the Buyer's
Group. The Companies shall be released from such Companies' Liabilities vis-
a-vis the Seller and Ivanhoe.

6.2 The Seller and/or the Guarantor shall be liable for any of the Companies'
Liabilities vis-a-vis parties other than the Seller and the Seller's Group that
did not appear but should have appeared on Schedule 4.

7.  GUARANTEE

7.1 In consideration of the Buyer entering into this Agreement the Guarantor, at
the request of the Seller and as principal obligor and not merely as surety,
hereby unconditionally guarantees to the Buyer and its successors, transferees
and assigns the due and punctual performance and observance by the Seller of

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all the Seller's obligations and the punctual discharge by the Seller of all the
Seller's liabilities to the Buyer under this Agreement. The forgoing is limited,
however, to the Seller's due formation, due authorization and execution of the
Agreement by the Seller and delivery to the Buyer of a valid and unencumbered
title to the Shares.

8.  COSTS

8.1 Except where this Agreement provides otherwise, each Party shall pay its own
costs relating to the negotiation, preparation, execution and performance by it
of this Agreement and of each document referred to in it.

9.  GENERAL

9.1 A variation of this Agreement is valid only if it is in writing and signed
by or on behalf of each Party.

9.2 The failure to exercise or delay in exercising a right or remedy provided by
this Agreement or by laws does not constitute a waiver of the right or remedy or
a waiver of other rights or remedies. No single or partial exercise of a right
or remedy provided by this Agreement or by law prevents further exercise of the
right or remedy or the exercise of another right or remedy.

9.3 The Parties' rights and remedies contained in this Agreement are cumulative
and not exclusive of rights or remedies provided by law.

9.4 Except to the extent that they have been performed and except where this
Agreement provides otherwise, the obligations contained in this Agreement remain
in force after Closing.

9.5 The Seller shall from time to time at its own cost, or on being required to
do so by the Buyer, now or at any time in the future, do or procure the doing of
all such acts and/or execute or procure the execution of all such documents in a
form satisfactory to the Buyer as the Buyer may reasonably consider necessary
for giving full effect to this Agreement and securing to the Buyer the full
benefit of the rights, powers and remedies conferred upon the Buyer in this
Agreement.

9.6 All obligations, agreements, covenants, undertakings or conditions in this
Agreement, together with any other documents referred to herein which have not
been done, observed or performed at or prior to or Closing shall remain in full
force and effect notwithstanding Closing.

9.7 If at any time any provision of this Agreement is or becomes invalid or
illegal in any respect such provision shall be deemed to be severed from this
Agreement but the validity, legality and enforceability of the remaining
provisions of this Agreement shall not be affected or impaired thereby.

9.8 The Buyer may assign its rights and benefits under this Agreement including
without limitation the Warranties, and the covenant in Clause 4.5 (together with
any cause of action arising in connection with any of them) to its successors in
title or to any member of the Buyer's Group.

9.9 This Agreement, together with the documents on Schedule 2, constitutes the
entire understanding between the Parties with respect to the subject matter of
this Agreement and supersedes all prior agreements, negotiations and discussions
between the Parties, their respective employees, agents and consultants.

10. NOTICES

10.1 Any notice, request or other communication to be given or made under this
Agreement by one Party to the other Party or Parties shall be in writing. The
notice, request or other communication may be delivered by hand, airmail,
facsimile or established courier service to the Party's address specified below
or at such other address as such Party notifies to the other Parties from time
to time and will be

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effective upon receipt or, in the case of delivery by hand or by established
courier service, upon refusal to accept delivery.

     For the Buyer: c/o BDO International, Galaxias Commercial Center, 4th
     floor, office 403, 33 Makarios III Avenue, 36 Agia Eleni St., P.O. Box
     22283

For the Seller:

     Kuban Petroleum Ltd, 9th Floor, Waterfront Centre, 200 Burrard Street,
     Vancouver, B.C. V6L 3L6, Tel: 016046888323, Fax: 0 16046826728

     Alternative address for communications by fax: 16046827 131, Tel:
     16046827737, attention: Goodman Phillps & Vineberg, 1900 -355 Burrard
     Street, Vancouver, V6C 2G8

For Guarantor:

     9th Floor, Waterfront Centre, 200 Burrard Street, Vancouver, B.C. V6C 3L6,
     Canada

Alternative address for communications by fax: 8 l-3-3947-53 19, attention:
Beverly Dowing

10.2 In the absence of evidence of earlier receipt, a notice or other
communication is deemed given:

     (a)   if delivered personally, when left at the address referred to in
           clause 8.1;

     (b)   if sent by mail except air mail, 12 days after posting it;

     (c)   if sent by air mail, six days after posting it;

     (d)   if sent by fax, on closing of its transmission.

11. GOVERNING LAW AND DISPUTE RESOLUTION

11.1 This Agreement shall be governed by and construed in accordance with the
laws of England and Wales.

11.2 Any dispute, controversy or claim arising out of or in connection with this
Agreement, or the breach, termination or invalidity thereof, shall be finally
settled by arbitration in accordance with the Rules of the Arbitration Institute
of the Stockholm Chamber of Commerce.

     The Tribunal shall be composed of three arbitrators.

     The place of arbitration shall be Stockholm, Sweden.

     The arbitral proceedings shall be conducted in the English language.

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12. COUNTERPARTS

This Agreement may be executed in any number of counterparts each of which when
executed and delivered is an original, but all the counterparts together
constitute the same document.

EXECUTED by the Parties:

Signed for the Seller

        /s/ MATTHEW LECHTZIER
--------------------------------------
          Matthew Lechtzier


Signed for the Buyer

     /s/ KONSTANTINOS KOUDELLARIS
--------------------------------------
       Konstantinos Koudellaris


Signed for the Guarantor

        /s/ MATTHEW LECHTZIER
--------------------------------------
          Matthew Lechtzier

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                              SCHEDULE 1 -- PART I

                         INFORMATION ABOUT GREAT PLAINS

1.   Registered number: 76786

2.   Date of incorporation: 2.2.1996

3.   Place of incorporation: Republic of Cyprus

4.   Address of registered office: 2, Sofouli Street, Chanteclair Building,
     office 205, Nicosia.

5.   Type of company: Private company limited by shares

6.   Authorized share capital: CYP 10,000. -- divided into 10,000 shares of
     CYP 1. -- each

7.   Issued share capital: CYP 1,000. -- divided in 1,000 shares of CYP 1. --
     each

8.   Directors: Gerald Burrows, Marios Eliades, Christina Drakou

9.   Secretary: Bensecra Limited

10.  Accounting reference date: 31.12.1999 (audited), 31.7.2000 (unaudited)

11.  Auditors: Deloitte & Touche

12.  Tax residence: Republic of Cyprus

13.  Bank accounts: None

14.  Charges: Nil

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                             SCHEDULE 1 -- PART II

                            INFORMATION ABOUT GLOBAL

1.   Registered number: 85 168

2.   Date of incorporation: 3.4.1997

3.   Place of incorporation: Republic of Cyprus

4.   Address of registered office: 2, Sofouli Street, Chanteclair Building, 2nd
     Floor, Nicosia 1096

5.   Type of company: Private company limited by shares

6.   Authorized share capital: CYP10,000 divided into 10,000 shares of CYP1. --
     each

7.   Issued share capital: CYP1,000 divided into 1,000 shares of CYP1. -- each

8.   Directors: Gerald Burrows, Marios Eliades, Christina Drakou

9.   Secretary: Bensecra Limited

10 . Accounting reference date: 31.12.1999 (audited), 31.7.2000 (unaudited)

11.  Auditors: Deloitte & Touche

12.  Tax residence: Republic of Cyprus

13.  Bank accounts: None

14.  Charges: Nil

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                                   SCHEDULE 2

                         ITEMS FOR DELIVERY AT CLOSING

1.   Executed Deed of Release of even date herewith between TOC, TNG, the
     Guarantor and the Seller.

2.   Executed Side Agreement with respect to adjustments of the tribunal's
     costs.

3.   Seller shall deliver to the Buyer the instruments of transfer of the Shares
     duly executed by the registered shareholders of Great Plains and Global.

4.   Seller shall deliver to the Buyer all original share certificates in the
     form required by the laws of Cyprus issued with respect to the Shares.

5    Seller shall deliver to the Buyer certificates of resignation (containing
     no claim clauses) duly executed under Cyprus law from each of the officers,
     if any, directors and secretaries of each of the Companies.

6.   Seller shall deliver to the Buyer, for each of the Companies:

     (i)    original or certified copies of resolutions of the board of
            directors of each of the Companies, made in accordance with clause
            3.3 of this Agreement;

     (ii)   original approval(s) of the Central Bank of Cyprus with respect to
            the Buyer as a new beneficial owner of the Shares; and

     (iii)  any powers of attorney under which any document required to be
            delivered by the Seller or the Guarantor has been executed.

7.   Seller shall deliver to the Buyer original corporate documents, and
     certified auditors' report and financial statements as of December 31,
     1999, unaudited certified financial statements as of July 31, 2000, and pro
     forma financial statements as of the date of Closing, and historical
     accounting records on computer discs for each of the Companies; originals
     (or notarized copies) of Tura corporate documents, facsimile copy of a
     notarized copy of the Tura Loan Agreement, as well as Xerox copies of
     corporate documents of Radonezh Petroleum.

8.   Each of the Guarantor and the Seller shall deliver to the Buyer certified
     copies of the resolution of their respective boards of directors, as well
     as of all other corporate authorizations and approvals, approving the
     execution, delivery and performance of this Agreement and the Deed of
     Release, and any other documents in implementation hereof, the consummation
     of the transactions contemplated hereby, and the authorizations of the
     persons signing this Agreement and the Deed of Release to sign them and to
     bind the respective parties thereby.

9.   The Seller shall deliver an unqualified letter of resignation from the
     auditors of each Company. The Seller shall deliver an original letter of
     confirmation of Great Plains' counsel in the Stockholm arbitration
     confirming the counsel's commitment to resign promptly after the Closing
     and to so inform the arbitral tribunal.

10.  The Seller shall deliver to the Buyer the following legal opinions the
     drafts of which shall be prior reviewed and shall be reasonably
     satisfactory to the Parties hereto and their legal counsels:

     (a)   the opinion of Goodman Phillips & Vineberg, a Canadian legal counsel
           for Guarantor, attesting to:

           (i)    the due organization and good standing of the Guarantor; the
                  Guarantor's corporate power and authority and taking of
                  necessary corporate actions to authorize its execution,
                  delivery and performance of this Agreement; and the due
                  authorization of the individual(s) executing this Agreement on
                  behalf of Guarantor;

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<PAGE>   13

           (ii)   its conclusion that no licenses, approvals, consents, filings
                  or registrations of any governmental authority are required
                  for the due execution, delivery or performance by the
                  Guarantor, of this Agreement; and

           (iii)  its conclusion the choice of governing law, arbitration
                  clauses and the forum for resolution of disputes in each of
                  this Agreement is valid and binding on the Guarantor.

     (b)   the opinion of Harney Westwood & Riegels, British Virgin Islands
           legal counsel for Seller, attesting to:

           (i)    the due organization and good standing of Seller; Seller's
                  corporate power and authority and taking of necessary
                  corporate actions to authorize its execution, delivery and
                  performance of this Agreement; and the due authorization of
                  the individual(s) executing this Agreement on behalf of
                  Seller;

           (ii)   its conclusion the choice of governing law, arbitration
                  clauses and the forum for resolution of disputes in each of
                  this Agreement is valid and binding on the Seller;

           (iii)  its conclusion that no approvals are required under the laws
                  of the British Virgin Islands for Seller to consummate the
                  transactions contemplated by this Agreement except for
                  necessary corporate actions.

     (c)   the opinion of Tassos Papadopoulos & Co., Cyprus legal counsel for
           the Companies, attesting to:

           (i)    the due organization and good standing of each of the
                  Companies; its conclusion that Seller is a beneficial owner of
                  all of the Shares in the Companies;

           (ii)   that Iver Management Limited and Bensecra Limited are the
                  legal owners of the Shares;

           (iii)  that the Shares are validly issued and fully paid;

           (iv)   at Closing, the valid and binding transfer of legal and
                  beneficial ownership of all of the Shares to Buyer.

11.  The Buyer shall deliver to the Seller and the Guarantor the opinion of
     Antis Triantafyllides & Sons, Cyprus legal counsel for Buyer attesting to:

     (i)   the due organization and good standing of Buyer; Buyer's taking of
           necessary corporate actions to authorize its execution, delivery and
           performance of this Agreement; and the due authorization of the
           individual(s) executing this Agreement on behalf of Buyer;

     (ii)  its conclusion the choice of governing law, arbitration clause and
           the forum for resolution of disputes in this Agreement is valid and
           binding on the Buyer;

     (iii) its conclusion that no approvals are required under the laws of
           Cyprus for Buyer to make payment and otherwise consummate the
           transactions contemplated by this Agreement, except for necessary
           corporate actions.

12.  Escrow Mandate dated 10 August 2000 between Kuban Petroleum Ltd, Ivanhoe
     Energy Inc, Stesana Enterprises Limited and Tassos Papadopoulos & Co.

                                       E-41
<PAGE>   14

                                   SCHEDULE 3

                                   WARRANTIES

1.    CAPACITY AND AUTHORITY

1.1   INCORPORATION AND EXISTENCE

1.1.1 The Guarantor represents and warrants that the Guarantor is duly
      organized, validly existing and in good standing under the laws of Canada,
      having all requisite corporate or other power and authority to execute and
      perform this Agreement.

1.1.2 Each of the Guarantor and the Seller represents and warrants that each of
      the Seller and the Companies is duly organized, validly existing under the
      laws of its jurisdiction of organization, having all requisite corporate
      or other power and authority to own the Shares and to hold Russian Shares
      on the books of the Companies.

1.1.3 Buyer represents and warrants that the Buyer is duly organized, validly
      existing and in good standing under the laws of its jurisdiction of
      organization, having all requisite corporate or other power and authority
      to make payment for the Shares.

1.2   RIGHT, POWER, AUTHORITY AND ACTION

1.2.1 The Guarantor represents and warrants that it has the right, power and
      authority and has taken all action necessary to validly execute and
      deliver, and to exercise its rights and perform its obligations under this
      Agreement.

1.2.2 Each of the Guarantor and the Seller represents and warrants that the
      Seller has the right, power and authority and has taken all action
      necessary to validly execute and deliver, and to exercise its rights and
      perform its obligations under, this Agreement and each document to be
      executed at or before Closing.

1.2.3 Buyer represents and warrants that it has the right, power and authority
      and has taken all action necessary to validly execute and deliver, and to
      exercise its rights and perform its obligations under, this Agreement,
      including its obligation to pay for and its right to acquire the Shares.

1.3   BINDING AGREEMENTS

      The Parties represent and warrant to each other that their respective
      obligations under this Agreement and each document to be executed at or
      before Closing are, or when the relevant document is executed will be,
      enforceable in accordance with their terms.

2.    INFORMATION

      Each of the Guarantor and the Seller represents and warrants as follows:

2.1   MATERIAL INFORMATION

      All material information about the Shares has been disclosed to the Buyer
      of the Shares.

3.    ASSETS AND LIABILITIES

      Each of the Guarantor and the Seller represents and warrants as follows:

3.1   THE SHARES

3.1.1 The Seller is the beneficial owner of the Shares.

3.1.2 The Shares comprise the whole of each Company's issued share capital, have
      been properly issued and are fully paid or credited as fully paid.

                                       E-42
<PAGE>   15

3.1.3 There is no Encumbrance, and there is no agreement, arrangement or
      obligation to create or give an Encumbrance, in relation to any of the
      Shares or unissued shares in the capital of either of the Companies. No
      person has claimed to be entitled to an Encumbrance in relation to any of
      the Shares.

3.1.4 Other than this Agreement, there is no agreement, arrangement or
      obligation requiring the creation, allotment, issue, transfer, redemption
      or repayment of, or the grant to a person of the right (conditional or
      not) to require the allotment, issue, transfer, redemption or repayment
      of, a share in the capital of either of the Companies (including, without
      limitation, an option or right of preemption or conversion of the Shares).

3.1.5.The shares of Radonezh Petroleum held on the books of Global Petroleum
      are not pledged or otherwise used as a collateral for securing any and
      all of the obligations of the Seller or Global Petroleum vis-a-vis third
      parties and/or the Seller's Group.

3.2   COMPANIES' LIABILITIES AS OF THE CLOSING

3.2.1 To the best of our knowledge there are no Companies' Liabilities other
      than those set forth on Schedule 4.

3.2.2 To the best of our knowledge as of the Closing there are no existing
      liabilities referred to in subsection (a) of the definition of the
      Companies' Liabilities resulting from or in connection with existing
      claims to the Companies.

4.    PAYMENT INSTRUMENT

4.1   Buyer represents and warrants that the Buyer's payment order presented at
      Closing for the total amount of the Purchase Price for the Shares is duly
      drawn and signed, valid and the purchase price is payable to the Seller
      immediately in accordance with its face, and is subject to no defense or
      dishonor on any ground whatever, and the account on which it is drawn
      contains sufficient funds to cover the Purchase Price and will so contain
      through the date of Closing and until the payment is honored.

4.2   Buyer undertakes, to obtain the presence of a duly authorized officer of
      the Bank of Cyprus to attend the Closing for the purpose of confirming the
      validity and irrevocability of the payment order issued to the Bank of
      Cyprus for the full amount of the Purchase Price and certification of the
      notice of credit of the full Purchase Price into the Trustee's account on
      the date of Closing net of any bank and other charges, costs and taxes
      that may be due at the time of debiting the Buyer's account.

                                       E-43
<PAGE>   16

                                   SCHEDULE 4

               ESTIMATED COMPANIES' LIABILITIES AS OF THE CLOSING

                               (August 10, 2000)

<TABLE>
<S>                                                           <C>
1.     GLOBAL PETROLEUM (Cyprus) LIMITED
1.1.   Actual liabilities (stated in US Dollars)
1.1.1. Accounts payable and accrued liabilities.............           0
1.1.2. Amount due to Kuban and/or Ivanhoe...................   8,460,930
1.2.   Contingent liabilities (in US Dollars)...............           0
                                                              ----------
         TOTAL..............................................   8,460,930
                                                              ==========
2.     GREAT PLAINS PETROLEUM (Cyprus) LIMITED
2.1.   Actual liabilities (stated in US Dollars)
2.1.1. Accounts payable and accrued liabilities.............           0
2.1.2. Amount due Kuban and/or Ivanhoe......................  56,559,470
2.2.   Contingent liabilities (in US Dollars)...............           0
                                                              ----------
         TOTAL..............................................  56,559,470
                                                              ==========
</TABLE>

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