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                                                                   Exhibit 10.13


                               SUNWING ENERGY LTD.
                           C/O CODAN SERVICES LIMITED
                                 CLARENDON HOUSE
                         2 CHURCH STREET, P.O. BOX 1022
                             HAMILTON HM1 1, BERMUDA


                                                              September 26, 2002
CITIC ENERGY INC.
c/o Room 2118 Hutchinson House
10 Harcourt Road
Hong Kong

Dear Sirs:

RE:      STRATEGIC DEVELOPMENT ALLIANCE

This letter is intended to reflect our recent discussions and, when executed and
delivered by each of us (execution and delivery by Sunwing Energy Ltd. deemed
made upon sending out this letter), will constitute a binding agreement ( the
"Agreement") between Sunwing Energy Ltd. ("Sunwing") and CITIC ENERGY INC., a
company incorporated under the laws of British Virgin Islands ("CITIC") in
respect of the matter more particularly described below.

The background to our Agreement is as follows:

(A)      CITIC is a wholly-owned subsidiary of CITIC International Holdings
         Limited, which in turn is a wholly-owned subsidiary of China
         International Trust & Investment Corporation, a trust and investment
         company that reports directly to the State Council of the People's
         Republic of China ("PRC");

(B)      the PRC government has expressed support for the Kyoto Protocol and for
         the overall objective of reducing air pollution in Chinese cities as a
         matter of priority;

(C)      the PRC government is a net importer of oil and it is a matter of
         strategic national importance to protect and enhance the supply of oil
         diversify sources of energy.

(D)      Sunwing is a wholly-owned subsidiary of Sunwing Holding Corporation
         which in turn is a wholly-owned subsidiary of Ivanhoe Energy Inc., a
         Canadian public company that has international investments and contacts
         in the oil and gas industry;

(E)      PRC and Canada have traditionally enjoyed strong business ties and
         excellent trade relations;


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(F)      Sunwing has the ability to assist CITIC in fulfilling its strategic
         objectives of the identifying and acquiring interests in key
         international oil and gas development projects and introducing proven,
         advanced oil and gas development and production technology to the
         domestic oil and gas industry in the PRC;

(G)      CITIC has the ability to assist SUNWING in fulfilling its strategic
         objectives of increasing its profile in Asian capital markets, gaining
         access to significant financing opportunities and financing
         opportunities and obtaining a listing on the Hong Kong Stock Exchange;
         and

(H)      in view of their respective objectives and abilities, a strategic
         alliance between Sunwing and CITIC offers significant potential
         benefits to both parties and their respective parent companies.


Based on the foregoing, we confirm the terms of our Agreement as follows:

1.       SUNWING OBJECTIVES

         The parties acknowledge that Sunwing's key corporate development
         objectives ( the "Sunwing Objectives") are as follows:

         (a)      to raise Sunwing's profile and to enhance Sunwing's
                  credibility among Asian institutional investors and in Asian
                  capital markets generally; and

         (b)      to list Sunwing's ordinary shares on the Hong Kong Stock
                  Exchange.

2.       CITIC OBJECTIVES

         The parties acknowledge that CITIC's key strategic objectives (the
         "CITIC Objectives") are as follows:

         (a)      to acquire interests in one or more international oil and gas
                  development projects; and

         (b)      to introduce "gas-to-liquids" technology and other advanced
                  technology oil and gas innovations to the domestic oil and gas
                  industry in the PRC.

3.       RECIPROCAL SERVICES

         Sunwing hereby engages CITIC, and CITIC agrees, to provide advice,
         assistance, expertise and other services (collectively, the "CITIC
         Services") to Sunwing in connection with Sunwing's pursuit of the
         Sunwing Objectives. CITIC hereby engages Sunwing, and Sunwing agrees,
         to provide advice, assistance expertise and other services (the
         "Sunwing Services") to CITIC in connection with CITIC's pursuit of the
         CITIC Objectives. The specific nature and scope of the CITIC Services
         and the Sunwing

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         Services will be as agreed from time to time between Sunwing and CITIC
         and will be tailored to expedite the timely achievement of the Sunwing
         Objectives and the CITIC Objectives, respectively.

4.       YUDONG PRODUCTION SHARING CONTRACT

         As part of the CITIC Services, CITIC shall use its best efforts,
         industrial expertise and PRC government contacts to support Sunwing's
         efforts to sign and obtain all necessary PRC governmental approvals
         for, a production sharing contract (the "Yudong PSC") with China
         National Petroleum Corporation and/or PetroChina Company Limited
         relating to the Yudong Block located in Eastern Chongqing Municipality,
         PRC. As soon as practical after the Agreement comes into effect, CITIC
         and Sunwing shall establish a new company ("Newco") under the laws of
         the British Virgin Islands that the parties will use as the corporate
         vehicle for signing and performing the Yudong PSC. The parties shall
         procure Newco to issue and allot a total of 100 ordinary shares at par
         value of US$1.00 each, which shall be owned by CITIC as to 30 shares
         ("CITIC's Newco Shares") and by Sunwing as to 70 shares.

5.       PUT AND CALL OPTIONS FOR THE CITIC'S NEWCO SHARES

         The parties hereby irrevocably grant each other the following shares
         exchange options with respect to CITIC's Newco Shares:

         (a)      CITIC shall have an option (the "CITIC Put Option") to
                  transfer to Sunwing, and Sunwing shall accept, unencumbered
                  legal and beneficial title to all of CITIC's Newco Shares in
                  exchange for Sunwing shares, which Sunwing shall issue and
                  allot, that will represent 20% of the total number of shares
                  in the capital of Sunwing issued immediately after completion
                  of the share exchange (and if Sunwing shall have more than one
                  class of shares issued prior to the completion of the share
                  exchange, CITIC shall receive upon exercise of the option by
                  it, for each such class, such number of Sunwing shares that
                  will represent 20% of the total number of shares in that class
                  issued immediately after the completion of the share
                  exchange), calculate on a fully-diluted basis, including all
                  outstanding options and/or warrants (vested or otherwise).
                  CITIC may exercise the CITIC Put Option at any time within 180
                  days after the effective date of the Yudong PSC by delivering
                  written notice to Sunwing (the "CITIC Put Notice")

         (b)      Sunwing shall have an option (the "Sunwing Call Option") to
                  require CITIC to transfer to Sunwing, unencumbered legal and
                  beneficial title to all of CITIC's Newco Shares in exchange
                  for Sunwing shares, which Sunwing shall issue and allot, that
                  will represent 20% of the total number of shares in the
                  capital of Sunwing issued immediately after completion of the
                  share exchange (and if Sunwing shall have more than one class
                  of shares issued prior to the completion of the share
                  exchange, CITIC shall receive upon exercise of the option by
                  Sunwing, for each such class, such number of Sunwing shares
                  that will represent 20% of the total number of shares in that
                  class issued immediately after the completion of the share
                  exchange), calculated

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                  on a fully-diluted basis, including all outstanding options
                  and/or warrants (vested or otherwise). Sunwing may exercise
                  the Sunwing Call Option at any time within 180 days after the
                  effective date of the Yudong PSC by delivering written notice
                  to CITIC (the "Sunwing Call Notice")


         (c)      The closing of the share exchange shall take place at the
                  office of Sunwing or its legal counsel within 30 days after
                  the date of the CITIC Put Notice or the Sunwing Call Notice,
                  as the case may be. At such closing: (i) CITIC shall deliver
                  to Sunwing duly endorsed share certificates and/or a stock
                  transfer power of attorney representing all of CITIC's Newco
                  Shares, together with directors resolutions, written
                  confirmations regarding CITIC's unencumbered ownership of all
                  of CITIC's Newco Shares, and such other relevant documents
                  that Sunwing or its legal counsel may reasonably request; and
                  (ii) Sunwing shares (in one or more classes, as the case may
                  be) duly registered in CITIC's name as fully paid and
                  non-assessable shares, together with directors resolutions,
                  written confirmations regarding the total number of issued
                  Sunwing shares, and such other relevant documents that CITIC
                  or its legal counsel may reasonably request.

6.       SUNWING BOARD REPRESENTATIVES

         (a)      Upon this Agreement taking effect, CITIC will be entitled to
                  nominate one (1) individual mutually acceptable to both
                  parties for appointment to Sunwing's board of directors

         (b)      If and when a closing of the CITIC Put Option or the Sunwing
                  Call Option occurs, CITIC will be entitled to nominate one (1)
                  additional individual mutually acceptable to both parties for
                  the appointment to Sunwing's board of directors.

7.       GENERAL REPRESENTATIONS AND WARRANTIES

         (I)      Each party hereby represents and warrants to each other party
                  as follows:

         (a)      it is duly incorporated and invalidly subsisting and in good
                  standing under the laws of its jurisdiction of incorporation
                  and is duly registered and license to carry on business in the
                  jurisdiction in which it carries on business and owns
                  property;

         (b)      it has the necessary corporate capacity and authority to
                  execute and deliver this Agreement and to observe and perform
                  its covenants and obligations hereunder and has taken all
                  necessary corporate action in respect thereof;

         (c)      this Agreement constitutes a legal, valid and binding contract
                  of the representing party enforceable against it in accordance
                  with its terms; and

         (d)      neither the execution and delivery of this Agreement, nor the
                  fulfillment of the terms


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                  hereof, will conflict with or result in a breach of any of the
                  terms, conditions or provisions of the constitutional
                  documents, resolutions of shareholders or directors, material
                  license or permits, or any material instrument to which the
                  representing party is a party or by which it is bound.

         (II)     Sunwing hereby agrees that the undertaking set out in this
                  sub-clause shall take effect upon CITIC acquiring Sunwing
                  shares under Clause 5 above (whether pursuant to the exercise
                  of the CITIC Put Option or the Sunwing Call Option). Sunwing
                  hereby undertakes that if it makes any offer or invitation to
                  any party (including to Sunwing's other shareholder(s)) to
                  subscribe for or acquire any of its share(s) (whether by way
                  of rights or otherwise), it shall make (and shall procure its
                  shareholders, directors and other persons having the right to
                  do so to consent to Sunwing to so make) a like offer or
                  invitation at the same time to CITIC on a pro rata basis at
                  the same price and on the same terms and conditions as its
                  offer or invitation to other potential investors.

8.       COMPLIANCE WITH LAWS

         The parties acknowledge, covenant and agree that all CITIC Services and
         all Sunwing Services will be carried out in strict compliance will all
         laws to which each of the parties hereto and their respective corporate
         affiliates is subject. Without limiting the generality of the
         foregoing, the parties acknowledge, covenant and agree that under no
         circumstances will the CITIC Services or the Sunwing Services involve
         or include any activities contrary to the Corruption of Foreign Public
         Officials Act (Canada) or the United States Foreign Corrupt Practices
         Act.

9.       APPROVALS

         (a)      Sunwing's obligations under this Agreement and the
                  effectiveness of this Agreement are subject to the approval of
                  the board of directors of Sunwing's ultimate parent company,
                  Ivanhoe Energy Inc., which approvals shall be obtained by
                  Sunwing within 15 days upon the execution and delivery of this
                  Agreement by CITIC. If such approval is not forthcoming, this
                  Agreement shall cease to have any legal effect.

         (b)      CITIC may, without assigning and reason and without any
                  liability for any compensation to Sunwing, terminate this
                  Agreement within 15 days after its execution of this Agreement
                  and upon such termination, this Agreement shall cease to have
                  any legal effect.


10.      EXPENSES

         The parties hereby agree that they will pay their own (and their
         representatives') respective fees and expenses incurred in connection
         with the negotiation, preparation, execution of this Agreement and the
         performance of their respective obligations hereunder.

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11.      PUBLIC ANNOUNCEMENTS

         Except as may be required under applicable law or stock exchange
         requirements, no press releases or other public disclosure relating to
         the transaction contemplated hereby shall Be issued, nor shall the
         terms of this Agreement be disclosed to third parties, other than to
         the representatives and advisors or either party, without the mutual
         consent of both parties hereto (which consent shall not be unreasonably
         withheld or delayed). All necessary press releases and other public
         disclosure in required for shall be submitted by the disclosing party
         prior to the dissemination thereof.

12.      GENERAL

         This Agreement is subject to the following additional terms and
         conditions:

         (a)      except as otherwise expressly provided herein, neither party
                  may assign any right, title or interest in this Agreement
                  without the written consent of the other party, and any
                  purported assignment without such consent will be void;

         (b)      this Agreement constitutes the entire agreement between
                  Sunwing and CITIC and supersedes every previous agreement,
                  communications, expectation, negotiation, representation,
                  warranty or understanding whether oral or written, express or
                  implied, statutory or otherwise, between the parties with
                  respect to the subject matter of this Agreement;

         (c)      each party will execute and deliver such further agreements
                  and documents and do such further acts and things as any party
                  reasonably requests to evidence, carry out or give full effect
                  to the intent of this Agreement;

         (d)      this Agreement is and will be deemed to have been made in
                  British Columbia, Canada for all purposes and will be governed
                  exclusively by and constructed and enforced in accordance with
                  the laws prevailing in British Columbia and rights and
                  remedies of the parties will be determined in accordance wit
                  those laws. Each of the parties hereby attorns to the
                  non-exclusive jurisdiction of the courts of British Columbia;

         (e)      this Agreement will ensure to the benefit of and binding upon
                  the respective legal representatives and successors of the
                  parties;

         (f)      this Agreement may be executed in any number of counterparts
                  with the same effect as if all parties to this Agreement had
                  signed the same document and all counterparts will construed
                  together and constitute one and the same documents;


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         (g)      words importing the masculine gender include the feminine or
                  neuter, words in the singular include the plural, words
                  importing a corporate entity include individuals, and vice
                  versa;

         (h)      a reference to "approval", "authorization" or "consent" means
                  written approval, authorization or consent;


         (i)      the headings in the Agreement are for the convenience only and
                  are not intended as a guide to interpretation of this
                  Agreement or any portion thereof; and

         (j)      all notices hereunder will be in writing and addressed to the
                  party for whom it is intended at the following address:



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       Sunwing:            Sunwing Energy Ltd.,
                           c/o Codan Services Limited
                           Clarendon House
                           2 Church Street, P.O. Box 1022
                           Hamilton HM11, Bermuda
                           Fax: 441-292-4720


                           with copy to:

                           Sunwing Energy Ltd.
                           Suite 654-999 Canada Place
                           Vancouver, BC  V6C 3E1
                           Fax:  1-604-682-2060

       CITIC:              CITIC ENERGY INC.
                           c/o Room 2118 Hutchinson House
                           10 Harcourt Road
                           Hong Kong
                           Fax: 852-2861-1901

                              *     *       *        *        *
 If the foregoing terms are acceptable to you, kindly sign and return a copy of
this letter by courier or facsimile transaction.


Yours truly,

SUNWING ENERGY LTD.

Per: "Patrick Chua"
    ------------------------------------------
Name:  Patrick Chua
Title: Co-Chairman


Agreed this 26th day of September, 2002

CITIC ENERGY INC.

Per: "Wang Jun"
     --------------------------------------
Name:  Wang Jun
Title: Director

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