<PAGE>
                                                                   EXHIBIT 10.25


                             SHAREHOLDERS AGREEMENT

                                     BETWEEN

                           ANGLO-AFRICAN ENERGY, INC.

                                       AND

                         TRANS-DOMINION HOLDINGS LIMITED



         THIS AGREEMENT is made and entered into as of this 1st day of August,
2000 ("Effective Date") by and between Anglo-African Energy, Inc., a corporation
organized and existing under the laws of Delaware ("AAE") and Trans-Dominion
Holdings Limited, a corporation organized and existing under the laws of the
Island of Jersey, Channel Islands, United Kingdom ("TDH"). AAE and TDH are
individually referred to as "Party" and collectively as the "Parties".

         WHEREAS, AAE and its Affiliates hold seventy-five percent (75%) and TDH
holds twenty-five percent (25%) of the issued and outstanding common stock ("TED
Shares") of Trinidad Exploration and Development Ltd. ("TED"); and

         WHEREAS, the Parties to this Agreement, together with those persons or
entities who shall acquire TED Shares after the date hereof and agree to be
bound by the terms hereof, desire to define their respective rights and
obligations as shareholders in TED.

         NOW THEREFORE, in consideration of the foregoing and of the mutual
premises, covenants and agreements contained herein, the parties hereto agree as
follows:

Article 1. Definitions

As used in this Agreement, the terms described below shall have the following
meanings:

1.1      Affiliate means a company, partnership or other legal entity which
         controls, or is controlled by or which is controlled by an entity which
         controls, a Party. Control means the ownership directly or indirectly
         of more than fifty (50) percent of the voting rights in a company,
         partnership or legal entity.

1.2      Agreed Interest Rate means interest compounded on a monthly basis, at
         the rate per annum equal to the one (1) month term, London Interbank
         Offered Rate (LIBOR rate) for U.S. dollar deposits, as published by The
         Wall Street Journal or if not published, then by the Financial Times of
         London, plus five (5) percentage points, applicable on



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         the first Business Day prior to the due date of payment and thereafter
         on the first Business Day of each succeeding calendar month. If the
         aforesaid rate is contrary to any applicable usury law, the rate of
         interest to be charged shall be the maximum rate permitted by such
         applicable law.

1.3      Agreement means this agreement, together with the Exhibits attached to
         this agreement, and any extension, renewal or amendment hereof agreed
         to in writing by the Parties.

1.4      Business Day means a day on which the banks in New York, NY and London,
         England are open for business.

1.5      Contracts means the Farmout Agreements, the Joint Operating Agreement
         between Petrotrin and TED dated October   , 1999, the Licenses and
         related Deeds of Assignment and any similar agreements for the
         exploitation of petroleum in the Republic of Trinidad and Tobago
         entered into by TED during the term of this Agreement.

1.6      Dollars means dollars of the United States of America.

1.7      Farmout Agreements means the Farmout Agreements for Petrotrin's
         Contract Area and TED's Contract Area dated October   , 1999.

1.8      Government means the government of the Republic of Trinidad and Tobago
         and any political subdivision or agency or instrumentality thereof.

1.9      License or Licenses means the Exploration and Production (Public
         Petroleum Rights) Licenses No. 9610 of 1970 and No. _____ of 1999 for
         the Southwest Peninsula granted to Petrotrin and the Exploration and
         Production (Private Petroleum Rights) License dated 16 February 1996
         granted to TED by the Government entitling them to explore and exploit
         the License Area and any future Exploration and Production Licenses
         obtained by the Company during the term of this Agreement.

1.8      License Area means the surface area that is described in each of the
         Licenses as such area may vary from time to time in accordance with and
         during the term of each such License.

1.9      Petrotrin means the Petroleum Company of Trinidad and Tobago, Ltd.

1.10     Transfer shall mean to sell, assign, convey, donate, transfer or
         otherwise dispose of or to contract to do any of the foregoing.



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<PAGE>
Article 2. Board of Directors

2.1      The Board of Directors of the Company shall consist of four directors.
         AAE shall be entitled to nominate three directors, and TDH shall be
         entitled to nominate one director. All corporate action shall be taken
         by a majority vote of the Board of Directors.

2.2      It is agreed that the initial directors shall be Peter G. Dilling,
         Duncan A. Lee, Christopher J. Ball and Joe Ciavarra.

2.3      Each Party agrees to use its best efforts to take all action necessary
         to cause the election of the directors nominated pursuant to Article
         2.1.

Article 3. Restrictions on Transfer or Encumbrance

3.1      Except as necessary to implement the provisions of Articles 10.3 and
         10.4, no Party shall Transfer any TED Shares or any right, title or
         interest therein or thereto and no purported Transfer shall be
         effective, except as provided in this Article 3.

3.2      The certificates representing the TED Shares shall have the following
         endorsement written, printed or stamped upon the face thereof:

                           "This certificate is issued subject to all the terms
                           and conditions of a Stockholders Agreement, dated as
                           of August 1, 2000 by and between the Company and all
                           of its Stockholders as of such date and this
                           certificate shall not be transferred except in
                           compliance with all of the terms and provisions of
                           said agreement, a copy of which is on file with the
                           Company, and this certificate shall, at all times,
                           remain subject to the terms and conditions thereof."

3.3      Nothing contained herein shall prohibit any Party from Transferring TED
         Shares to an Affiliate, provided such transferee agrees in writing to
         be bound by the terms of this Agreement.


3.4      Any Transfer by a Party of all or a portion of its TED Shares, whether
         directly or indirectly by assignment, merger, consolidation, or sale of
         stock, or other conveyance, other than with or to an Affiliate, shall
         be subject to the following procedure:

         (A) Once the transferor Party and a proposed transferee have fully
         negotiated the final terms and conditions of a Transfer of all or a
         portion of its TED Shares, such final terms and conditions shall be
         disclosed in detail to the other Party in a notice from the transferor.
         The other Party shall have the right to acquire the TED Shares



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<PAGE>
         from the transferor on the same terms and conditions agreed to by the
         proposed transferee it within thirty (30) days of the transferor's
         notice, such Party delivers to all other Parties a counter-notification
         that it accepts the agreed upon terms and conditions of the transfer
         without reservations or conditions. If the other Party does not deliver
         such counter-notification, the transfer to the proposed transferee may
         be made, subject to the other provisions of this Article III, under
         terms and conditions no more favorable to the transferee than those set
         forth in the notice to the other Party, provided that the transfer
         shall be concluded within one hundred eighty (180) days from the date
         of the notice plus such reasonable additional period as may be required
         to secure Governmental approvals.

         (B) In the event that a Party's proposed Transfer of part or all of its
         TED Shares involves consideration other than cash or involves other
         properties included in a wider transaction (package deal) then the TED
         Shares (or part thereof) shall be allocated a reasonable and
         justifiable cash value by the transferor in any notification to the
         other Party.

Article 4. Voting of TED Shares

4.1      Each Party agrees to vote its respective TED Shares so as to carry out
         and make effective all of the terms and provisions of this Agreement.

4.2      All shareholder action may be taken by majority vote of the
         shareholders except for the disposition of all of the assets of TED,
         the liquidation of TED or any transactions between TED and a Party or
         any Affiliate of a Party, other than in the ordinary course of
         business. As used herein, the term "ordinary course of business" means
         any activity that is related to the exploration, production, storage,
         transportation and sale of petroleum, including without limitation, the
         acquisition of additional petroleum rights licenses or producing
         properties. For purposes of the foregoing sentence, it is understood
         and agreed by the Parties that the acquisition of petroleum rights or
         licenses from a Party or its Affiliate is not a transaction in the
         ordinary course of business. In the event of a sale of petroleum to a
         Party, such sale shall be at the current market value f.o.b. the
         delivery point. In the event that TDH disagrees with a decision of the
         majority of the shareholders, and as a result of such disagreement
         decides to exercise its rights under Article 10.3, the Parties agree
         that, to the extent practicable, TDH's beneficial interest in the
         Licenses and the Contracts shall be recognized as of the date it gives
         notice of its desire to exercise its rights under Article 10.3,
         adjusted in accordance with Article 6 for any subsequent loans or
         investments in the Company made by the Parties.

4.3      In lieu of a meeting, any Party may submit any proposal to the other
         Party for a vote by notice. Each Party shall communicate its vote by
         notice to the other parties within five (5) Business Days. Any Party
         failing to communicate its vote within the prescribed time period shall
         be deemed to have voted in favor of such proposal.



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Article 5. Indemnity

5.1      In the event that the Parties guarantee any loans on behalf of TED and
         such guarantee is joint or joint and several, then the Parties hereby
         agree to indemnity any Party who is required to make payments pursuant
         to the guarantee to the extent that it makes payments in excess of its
         proportionate share of the guaranteed amount.

5.2      It is the intent of the Parties that the participation and liability of
         any guaranteed amount as between the Parties themselves shall be in
         proportion to the respective number of issued and outstanding TED
         Shares owned by the Party.

5.3      As used herein, the term "guaranteed amount" shall mean the principal
         amount of the loan, including any interest thereon, which is jointly or
         jointly and severally guaranteed by the Parties.

Article 6. Additional Capital Contributions or Loans to TED

6.1      For purposes of this Article 6, each Party has contributed or has been
         deemed to contribute to TED the amount set forth in Exhibit A hereto.

6.2      From and after the Effective Date of this Agreement, AAE agrees to lend
         to TED such amounts and at such times as may be necessary to fund the
         work programs required under the License and the Contracts as well as
         to fund other operating expenses of TED in an aggregate amount not to
         exceed four million Dollars ($4,000,000). This loan will bear interest
         at the rate of eight percent (8%) per annum and will be repayable out
         of the proceeds of oil sales in accordance with the terms of the Loan
         Agreement attached hereto as Exhibit B.

6.3      Any additional funding that is required by TED in excess of the
         $4,000,000 referred to in Article 6.2 above shall be contributed by the
         Parties pro rata to their shareholding in TED. If one of the Parties
         fails to pay, when due, its pro rata share of the required amounts,
         such Party shall be in default under this Agreement ("Defaulting
         Party"). The non-Defaulting Party shall promptly give notice of such
         default to the Defaulting Party (the "Default Notice"). The amount not
         paid by the Defaulting Party shall bear interest from the date due
         until paid in full at the Agreed Interest Rate.

                     [REST OF PAGE INTENTIONALLY LEFT BLANK]



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6.4      If the Defaulting Party fails to remedy its default by the fifteenth
         (15th) day following the date of the Default Notice, then without
         prejudice to any other rights available to the non-Defaulting Party to
         recover amounts owing to it under this Agreement, the non-Defaulting
         Party shall have the option, exercisable at anytime thereafter, to have
         its percentage shareholding in TED recalculated as follows: The
         Defaulting Party's percentage shareholding will be reduced to that
         percentage resulting from dividing such Defaulting Party's net capital
         contributions by the aggregate net capital contributions of both the
         Defaulting and Non-Defaulting Parties. For purposes of this
         calculation, the term "net capital contributions" shall mean that
         amount shown on Exhibit A plus any additional amounts in excess of the
         $4,000,000 referred to in Article 6.2 contributed to the capital of TED
         as either loans or as equity, less the amount of any such loans which
         are repaid or the amount of any such equity which is redeemed. The
         percentage shareholding of the non-Defaulting Party shall be increased
         by a like amount.

6.5      The Parties agree that the non-Defaulting Party shall be issued such
         additional number of TED Shares as may be necessary to reflect the
         change in such non-Defaulting Party's percentage interest in the
         ownership of TED resulting from the application of the foregoing
         formula. The Defaulting Party shall, without delay, following any
         request from the non-Defaulting Party, do any and all acts required to
         be done and execute any and all documents and take such other actions
         as may be necessary in order to effect a prompt and valid issuance of
         such additional TED Shares to the non-Defaulting Party. The acceptance
         by non-Defaulting Party of any such additional TED Shares shall not
         limit any rights or remedies that the non-Defaulting Party has to
         recover any other amounts (including interest) that may be owing under
         this Agreement, the Stock Purchase Agreement executed by the Parties
         and others as of date hereof, or any of the Contracts by the Defaulting
         Party.

Article 7. Term

7.1      Except as otherwise provided in Article 7.2 below, this Agreement shall
         continue for as long as both Parties remain as shareholders in TED.

7.2      This Agreement shall automatically terminate upon the happening of any
         of the following contingencies:

         (A)      Dissolution of TED;

         (B)      The consummation of any merger or consolidation to which TED
                  is a party, unless immediately following such merger or
                  consolidation, the Parties shall own all of the voting power
                  of the outstanding capital stock of the surviving or resulting
                  company;

         (C)      The unanimous written consent of both Parties to the
                  termination of this Agreement;

         (D)      Commencement by TED of a voluntary bankruptcy which proceeding
                  results in the Parties being required to relinquish control
                  over the day to day affairs and/or operations of TED;



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         (E)      The granting of relief against TED in an involuntary
                  bankruptcy proceeding; or

         (F)      An assignment for the benefit of creditors made by TED which
                  results in the Parties being required to relinquish control
                  over the day to day affairs and/or operations of TED.

         (G)      If one or both Parties take title to their interests in the
                  Contracts and Licenses directly.

Article 8. Notices

8.1      Except as otherwise specifically provided, all notices authorized or
         required between the Parties by any of the provisions of this
         Agreement, shall be in writing, in English and delivered in person or
         by courier service or by any electronic means of transmitting written
         communications which provides written confirmation of complete
         transmission, and addressed to such Parties as designated below. Oral
         communication does not constitute notice for purposes of this
         Agreement, and telephone numbers for the Parties are listed below as a
         matter of convenience only. The originating notice given under any
         provision of this Agreement shall be deemed delivered only when
         received by the Party to whom such notice is directed, and the time for
         such Party to deliver any notice in response to such originating notice
         shall run from the date the originating notice is received. Each Party
         shall have the right to change its address at any time and/or designate
         that copies of all such notices be directed to another person at
         another address, by giving written notice thereof to the other Party.

If to Anglo-African Energy, Inc.:

         Anglo-African Energy, Inc.
         29 Queens Park West
         Port of Spain
         Trinidad, W.I.
         Attention: Peter G. Dilling
         Telephone: To be advised
         Telecopier: To be advised

With a copy to:

         Aitken Irvin Berlin & Vrooman, LLP
         2 Gannett Drive
         White Plains, NY 10604
         Telephone: 914-694-5717
         Telecopier: 914-694-1647
         Attention: Alan D. Berlin, Esq.




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If to Trans Dominion Holdings Limited:

         Trans Dominion Holdings Limited:
         Piermont House
         33/35 Pier Road
         St. Helier
         Jersey
         Channel Islands
         JE4 8QZ
         Fax: +44-1534-33536
         Attn: Jeremy Johnson

With a copy to:

         Madison Oil Company
         9400 North Central Expressway
         Suite 1209
         Dallas, Texas 75231
         Attention: J. Ciavarra
         Tel: 214-373-6000
         Fax: 214-373-6071

With a further copy to:

         Meighen Demers
         200 King Street W, Suite 1100
         Toronto, Canada M5H 3T4
         Attention: Rick Sutin
         Tel: 416-340-6021
         Fax: 416-977-5239

Article 9. Applicable Law and Dispute Resolution

9.1      This Agreement shall be governed by and construed in accordance with
         the domestic laws of the State of New York without giving effect to any
         choice or conflict of law provision or rule that would cause the
         application of the laws of any jurisdiction other than the State of New
         York.

9.2      Any dispute, controversy or claim arising out of or in relation to or
         in connection with this Agreement including without limitation any
         dispute as to the construction, validity, interpretation,
         enforceability or breach of this Agreement that is not otherwise
         resolved through negotiation shall be exclusively and finally settled
         by arbitration, and any Party may submit such a dispute, controversy or
         claim to arbitration. If the claims giving rise to the arbitration is
         the direct result of and/or is based on the identical claims submitted
         for adjudication in an arbitration arising out of an agreement to which
         one of the Parties is a party, then the claims arising under this



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         Agreement shall be submitted for adjudication in such other arbitration
         proceeding. If such is not the case, or if the arbitrators in the other
         arbitration proceeding can not or will not take jurisdiction of such
         claims, then the following provisions shall apply to any arbitration
         proceeding instituted under this Agreement.

9.3      A single arbitrator shall be appointed by unanimous consent of the
         Parties. If the Parties cannot reach agreement on an arbitrator within
         thirty (30) days of the submission of a Notice of Arbitration, the
         appointing authority shall be the American Arbitration Association,
         which shall appoint an independent arbitrator who does not have any
         financial interest in the dispute, controversy or claim.

9.4      Unless otherwise expressly agreed to in writing by the parties to the
         arbitration proceedings:

         (A) The arbitration proceedings shall be held in New York, New York;

         (B) The arbitrator shall be and remain at all times wholly independent
         and impartial;

         (C) The arbitration proceedings shall be governed by the U.S.
         Arbitration Act, 9 U.S.C. Sections 1-16, and be conducted in accordance
         with the Commercial Arbitration Rules of the American Arbitration
         Association then in effect;

         (D) Any procedural issues not determined under the arbitral rules
         selected pursuant to this Agreement shall be determined by the law of
         the place of arbitration, other than those laws which would refer the
         matter to another jurisdiction;

         (E) Each party shall be responsible for its own costs of the
         arbitration proceedings (including attorneys fees and costs); and

         (F) Judgment upon the award rendered by the arbitrator may be entered
         in any court having jurisdiction thereof.

Article 10. Miscellaneous

10.1     Unless otherwise unanimously agreed by the Parties, TED will engage
         only in exploration and production activities, including related
         storage and transportation functions.

10.2     AAE and TDH will each have the right, but not the obligation, to enter
         into other petroleum activities in Trinidad and Tobago in addition to
         the Licenses as well as non-petroleum related projects and activities,
         all exclusive of TED.

10.3     If one or both Parties wish to hold all of their interests in the
         Licenses and the Contracts directly rather than through TED, the
         Parties agree to cooperate with each other and to execute all necessary
         documentation in a timely manner to achieve such result in an
         appropriate manner consistent with applicable laws and



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         regulations, the terms of the Licenses and all necessary Government
         approvals, including without limitation, the approval of Petrotrin.

10.4.    In the event that the Parties wish to transfer an interest in TED to a
         third party (or if they hold their interests in the Licenses directly,
         an interest in the Licenses), then each Party shall reduce its interest
         either in TED or in the Licenses, as the case may be, pro-rata.

10.5     Headings and titles are for convenience or reference only and shall not
         control the construction or interpretation of any provision hereof.

10.6     The Parties agree that the management costs of TED and charges made to
         TED by the Parties or their Affiliates shall be fair and reasonable.
         All such charges shall be subject to audit by either Party at such
         Party's sole expense. If there is a disagreement with regard to the
         charges being made by one of the Parties, then the provisions of the
         Accounting Procedure of the Joint Operating Agreement shall govern.

10.7     TDH shall on request, be entitled to copies of all data of TED
         including, but not limited to, financial and accounting information,
         seismic data and interpretations, well logs and reports and any other
         technical data or reports, contracts and agreements. The Parties agree
         that the confidentiality provisions of the Joint Operating Agreement
         shall govern the use of all such information and data. The cost of
         copying any such information hereunder, shall be at the sole expense of
         TDH.

10.8     All pronouns and any variations thereof shall be deemed to refer to the
         masculine, feminine, or neuter, singular or plural, as the identity of
         the person or persons or entity or entities may require. Each defined
         term herein may be used in either the singular or plural form whether
         or not so defined.

10.9     This Agreement contains the entire agreement of the parties with
         respect to the subject matter hereof and no interpretation, change,
         termination or waiver of, or extension of time for performance under,
         any provision of the Agreement shall be binding upon any party unless
         in writing and signed by the party intended to be bound thereby.

10.10    No waiver of or failure to exercise any right under, or default or
         extension of time for performance under, any provision of this
         Agreement shall affect the right of any party to exercise any
         subsequent right under or otherwise enforce said provision or any other
         provision hereof or to exercise any right or remedy in the event of any
         other default whether or not similar.

10.11    In case any one or more of the provisions contained in this Agreement
         shall be invalid or unenforceable in any respect, the validity and
         enforceability of the remaining provisions contained herein shall not
         in any way be affected or impaired



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         thereby and the parties will attempt to agree upon a valid and
         enforceable provision which shall be a reasonable substitute for such
         invalid or unenforceable provision in light of the tenor of this
         Agreement, and, upon so agreeing, shall incorporate such substitute
         provision in this Agreement.

10.12    This Agreement may be executed in one or more counterparts, all of
         which together shall constitute a single instrument. Each counterpart
         shall constitute an original, any one of which may be introduced in
         evidence or used for any other purposes without production of its
         duplicate counterpart.

10.13    The Parties shall execute and deliver all such future instruments and
         take such other and further action as may be reasonably necessary or
         appropriate to carry out the provisions of this Agreement and the
         intention of the Parties as expressed herein.


                     [REST OF PAGE INTENTIONALLY LEFT BLANK]



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IN WITNESS WHEREOF, the parties hereto have executed and delivered this
Agreement as of the day and year first above written.


Anglo-African Energy, Inc.                  Trans-Dominion Holdings Limited


By: /s/ PETER G. DILLING                    By: /s/ J. JOSEPH CIAVARRA
   -------------------------------             ---------------------------------
Peter G. Dilling                            J. Joseph Ciavarra
President                                   Pres & CEO


LIST OF EXHIBITS

Exhibit A                     Shareholdings and Initial Capital Contributions
Exhibit B                     Loan Agreements



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<PAGE>

                                    EXHIBIT A

                             SHAREHOLDERS AGREEMENT
                                     BETWEEN
                           ANGLO-AFRICAN ENERGY, INC.
                                       AND
                         TRANS-DOMINION HOLDING LIMITED

<Table>
<Caption>
                                                                                         Capital Contribution For
Shareholder                                       TED Shares Owned                       Purposes of Article 6
-----------                                       ----------------                       ------------------------
<S>                                               <C>                                    <C>
Anglo-African Energy, Inc.                        7,500                                  US$3,000,000
Trans-Dominion Holdings Limited                   2,500                                  US$1,000,000
</Table>



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