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                                                                    Exhibit 99.4

                                  [LOGO] HARKEN
                               Energy Corporation

                             Shares of Common Stock

                           Offered Pursuant to Rights

                         Distributed to Security Holders

                 , 2003
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To Securities Dealers, Commercial Banks,
     Trust Companies and Other Nominees:

          This letter is being distributed to securities dealers, commercial
banks, trust companies and other nominees in connection with the rights offering
(the "Rights Offering") by Harken Energy Corporation (the "Company") of shares
of its Common Stock (as such term is defined below), pursuant to
non-transferable subscription rights (the "Rights") distributed to all holders
of record (collectively, the "Recordholders") of shares of its common stock, par
value $0.01 per share (the "Common Stock"), and shares of its Series G1
preferred stock and Series G2 preferred stock (collectively, the "Preferred
Stock") at the close of business on               , 2003 (the "Record Date").
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The Rights are described in the Company's Prospectus dated                , 2003
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(the "Prospectus").

          In the Rights Offering, the Company is offering an aggregate of
                                                                          -----
shares of Common Stock, as described in the Prospectus.

          The Rights will expire, if not exercised, at 5:00 p.m., New York City
time, on               , 2003, unless extended in the sole discretion of the
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Company (as it may be extended, the "Expiration Date").

          Each Right allows you to subscribe for       shares of Common Stock.
                                                 -----
The Subscription Price of the Rights is $    per Right (or $    per share of
                                         ---                ---
Common Stock) (the "Subscription Right").

          If any shares of Common Stock offered in the Rights Offering remain
unsubscribed after the Rights Offering, Lyford Investments Enterprises Ltd., a
creditor of the Company, has agreed to purchase all such shares at the
Subscription Price.

          The Rights are evidenced by a non-transferable Rights certificate (a
"Rights Certificate") registered in your name or the name of your nominee. Each
beneficial owner of shares of Common Stock registered in your name or the name
of your nominee is entitled to one Right for each share of Common Stock owned by
such beneficial owner as of the close of business on the Record Date (or in the
case of the Preferred Stock, one Right for each share of Common Stock issuable
upon conversion).

          Enclosed are copies of the following documents:

          1.   Prospectus;

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          2.   Instructions as to Use of Harken Energy Corporation Rights
               Certificates (including a Notice of Guaranteed Delivery for
               Rights Certificates Issued by Harken Energy Corporation and
               Guidelines for Request for Taxpayer Identification Number and
               Certification on Substitute Form W-9);

          3.   A form of letter that may be sent to your clients for whose
               accounts you hold shares of Common Stock registered in your name
               or the name of your nominee, with an attached form of
               instruction;

          4.   Notice of Guaranteed Delivery for Rights Certificates Issued by
               Harken Energy Corporation; and

          5.   A return envelope addressed to American Stock Transfer & Trust
               Company, the Subscription Agent.

          We are asking you to contact those of your clients for whose accounts
you hold shares of Common Stock registered in your name or the name of your
nominee to obtain their instructions with respect to the Rights.

          All commissions, fees and other expenses (including brokerage
commissions and transfer taxes), other than fees and expenses of the
Subscription Agent, incurred in connection with the exercise of the Rights will
be for the account of the holder of the Rights, and none of such commissions,
fees or expenses will be paid by the Company or the Subscription Agent.

          Your prompt action is requested. To exercise Rights, you should
deliver the properly completed and signed Rights Certificate (or the Notice of
Guaranteed Delivery if you are following the Guaranteed Delivery Procedures),
with payment of the Subscription Price in full for each share of Common Stock
subscribed for, to the Subscription Agent, as indicated in the Prospectus. The
Subscription Agent must receive the Rights Certificate or Notice of Guaranteed
Delivery with payment of the Subscription Price prior to 5:00 p.m., New York
City time, on the Expiration Date. A Rights holder cannot revoke the exercise of
its Rights. Rights not exercised prior to the Expiration Date will expire.

          Additional copies of the enclosed materials may be obtained from the
Subscription Agent. The Subscription Agent's telephone number is (718) 921-8237.

                                                  Very truly yours,

                                                  HARKEN ENERGY CORPORATION

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Nothing in this prospectus or in the enclosed documents shall constitute you or
any person as an agent of Harken Energy Corporation, the Subscription Agent or
any other person making or deemed to be making offers of the securities issuable
upon valid exercise of the rights, or authorize you or any other person to make
any statements on behalf of any of them with respect to the offering except for
statements made in the prospectus.

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