Document:

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                                                                   Exhibit 10.53

                            HARKEN ENERGY CORPORATION
                              SEVERANCE AGREEMENT
                              -------------------

THIS SEVERANCE AGREEMENT (the "Agreement") is made and entered into this ____
day of July, 2003 by and between HARKEN ENERGY CORPORATION, a Delaware
corporation, whose principal office is 580 WestLake Park Blvd., Suite 600,
Houston, Texas 77079 ("the Company") and ELMER A. JOHNSTON, an individual
employee of the Company, whose home address is 13414 Layton Castle Lane,
Cypress, Texas 77429, (the "Employee").

WHEREAS, the Employee is, as of the Date hereof, in the employ of the Company
and is an executive officer of the Company on whom the Company relies and whom
the Company desires to retain in its employment; and

WHEREAS, the Company and Employee have reached an agreement with respect to
certain severance incentives as more fully provided hereinafter.

NOW THEREFORE, for and in the mutual considerations recited and acknowledged by
both parties hereto, the Company and the Employee agree as follows:

1.   Severance Upon Involuntary Termination:
     --------------------------------------

In the event that Employee is Involuntarily terminated by the Company during the
Term of this Agreement, then the Company will pay to Employee a sum of money, IN
ADDITION TO any and all severance pay and related compensation such Employee is
entitled to receive under the policies in effect by the Company on the date of
this Agreement, the additional amount equal to nine (9) months salary.

The salary used to compute this Additional Severance will be the greater of
either the Employee's salary at the time of the termination or Employee's salary
as of the date of this Agreement.

The payment of this Additional Severance will become due to Employee from the
Company upon any event of involuntarily termination during the Term, whether it
be with or without cause, or an event of individual involuntary termination or
in connection with a layoff, plant closing or force reduction.

2.   Voluntary Termination:
     ---------------------

In the event that Employee elects for any reason to voluntarily terminate his
employment with the Company during the Term, then in such event the Company will
pay to Employee a sum of money equal to six (6) months salary as of that date of
her voluntarily termination.

3.   Constructive Termination:
     ------------------------

In the event that, during the term hereof, the Company shall decrease by more
than ten percent (10%) Employee's salary from the amount set as of the date
hereof, such action shall

<PAGE>

be construed as a constructive termination under this Agreement which shall
trigger the obligation of the Company to pay to Employee the Additional
Severance amount irregardless of whether Employee's actual employment is
terminated or continued. Any single decrease of salary in excess of 10% or any
series of decreases during the Term, which in the aggregate equal more than 10%,
will be a constructive termination hereunder and give rise to the provisions of
this Section 3.

4.   No Guaranty of Employment:
     -------------------------

This Agreement shall not constitute nor be construed nor interpreted as any
guarantee nor contract for continued employment of Employee with the Company,
any subsidiary or any successor company. The parties stipulate that as to any
rights of ongoing or future employment, that the Employee is an employee at
will.

5    Term of Agreement:
     -----------------
Unless otherwise agreed to in writing by the parties hereto, this Agreement
shall be in effect from the date first set forth above and shall continue
through and including June 1, 2004. At the expiration of the Term this Agreement
may be extended, modified or renegotiated only upon the mutual written agreement
of both.

6.   Cancellation of Global Severance Agreement:
     ------------------------------------------

As partial consideration for this Agreement, Employee hereby cancels and
releases the Severance Agreement previously in effect by and between Employee
and the Company's subsidiary, Global Energy Development PLC (the "Global
Agreement") and agrees that the Company, its subsidiaries and affiliates shall
hereafter have no obligation nor liability to Employee pursuant to the Global
Agreement.

7.   Parties:
     -------

This Agreement shall be binding on the parties hereto and shall further be
binding upon the successors, assigns, parent corporations or subsidiary
corporations of the Company, and shall further inure to the benefit of the heirs
and assigns of Employee.

8.   Governing Law:
     -------------

This Agreement shall be governed by and interpreted in accordance with the laws
of the State of Texas, without giving effect to the principles of conflicts of
law thereof.

9.   Entire Agreement:
     ----------------
This Agreement constitutes the entire agreement between the parties with respect
to the subject matter hereof and replaces, restates in full and supersedes all
other prior agreements and understandings, both written and oral.

Executive Severance Agreement--Johnston 2
Version 7/22/03

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IN WITNESS whereof this Agreement has been executed the day and year first above
written.

HARKEN ENERGY CORPORATION (the Company)

By:   /s/ Mikel D. Faulkner
   -------------------------------
Name: Mikel D. Faulkner
Its:  President and CEO

ELMER JOHNSTON (the Employee)

/s/ Elmer Johnston
------------------

Executive Severance Agreement--Johnston 3
Version 7/22/03<PAGE>
                                                                   Exhibit 10.54

                            HARKEN ENERGY CORPORATION
                              SEVERANCE AGREEMENT
                              -------------------

THIS SEVERANCE AGREEMENT (the "Agreement") is made and entered into this ____/
/day of July, 2003 by and between HARKEN ENERGY CORPORATION, a Delaware
corporation, whose principal office is 580 WestLake Park Blvd., Suite 600,
Houston, Texas 77079 ("the Company") and RODGER EHRLISH an individual employee
of the Company, whose home address is 22119 Broken Pebble Ct., Katy, Texas
77079, (the "Employee").

WHEREAS, the Employee is, as of the Date here of, in the employ of the Company
and is an executive employee on whom the Company relies and whom the Company
desires to retain in its employment; and

WHEREAS, the Company and Employee have reached an agreement with respect to
certain severance incentives as more fully provided hereinafter.

NOW THEREFORE, for and in the mutual considerations recited and acknowledged by
both parties hereto, the Company and the Employee agree as follows:

1.   Severance Upon Involuntary Termination:
     --------------------------------------

In the event that Employee is involuntarily terminated by the Company during the
Term of this Agreement, then the Company will pay to Employee a sum of money, IN
ADDITION TO any and all severance pay and related compensation such Employee is
entitled to receive under the policies in effect by the Company on the date of
this Agreement, the additional amount equal to nine (9) months salary.

The salary used to compute this Additional Severance will be the greater of
either the Employee's salary at the time of the termination or Employee's salary
as of the date of this Agreement.

The payment of this Additional Severance will become due to Employee from the
Company upon any event of involuntarily termination during the Term, whether it
be with or without cause, or an event of individual involuntary termination or
in connection with a layoff, plant closing or force reduction.

2.   Voluntary Termination:
     ---------------------

In the event that Employee elects for any reason to voluntarily terminate
his/her employment with the Company during the Term, then in such event the
Company will pay to Employee a sum of money equal to six (6) months salary as of
that date of her voluntarily termination.

3.   Constructive Termination:
     ------------------------

In the event that, during the term hereof, the Company shall decrease by more
than ten percent (10%) Employee's salary from the amount set as of the date
hereof, such action shall be construed as a constructive termination under this
Agreement which shall trigger the obligation of the Company to pay to Employee
the Additional Severance amount due under

<PAGE>

involuntary termination irregardless of whether Employee's actual employment is
terminated or continued. Any single decrease of salary in excess of 10% or any
series of decreases during the Term, which in the aggregate equal more than 10%,
will be a constructive termination hereunder and give rise to the provisions of
this Section 3.

4.   No Guaranty of Employment:
     -------------------------

This Agreement shall not constitute nor be construed nor interpreted as any
guarantee nor contract for continued employment of Employee with the Company,
any subsidiary or any successor company. The parties stipulate that as to any
rights of ongoing or future employment, that the Employee is an employee at
will.

5.   Term of Agreement:
     -----------------

Unless otherwise agreed to in writing by the parties hereto, this Agreement
shall be in effect from the date first set forth above and shall continue
through and including June 1, 2004. At the expiration of the Term this Agreement
may be extended, modified or renegotiated only upon the mutual written agreement
of both.

6.   Cancellation of Global Severance Agreement:
     ------------------------------------------

As partial consideration for this Agreement Employee hereby cancels and releases
the Severance Agreement previously in effect by and between Employee and the
Company's subsidiary, Global Energy Development PLC (the "Global Agreement") and
agrees that the Company, its subsidiaries and affiliates hereafter shall have no
further obligation or liability to Employee pursuant to the Global Agreement.

7.   Parties:
     -------

This Agreement shall be binding on the parties hereto and shall further be
binding upon the successors, assigns, parent corporations or subsidiary
corporations of the Company, and shall further inure to the benefit of the heirs
and assigns of Employee.

8.   Governing Law:
     -------------

This Agreement shall be governed by and interpreted in accordance with the laws
of the State of Texas, without giving effect to the principles of conflicts of
law thereof.

9.   Entire Agreement:
     ----------------

This Agreement constitutes the entire agreement between the parties with respect
to the subject matter hereof and replaces, restates in full and supersedes all
other prior agreements and understandings, both written and oral.

Executive Severance Agreement--Johnston 2
Version 7/22/03

<PAGE>

IN WITNESS whereof this Agreement has been executed the day and year first above
written.

HARKEN ENERGY CORPORATION (the Company)

By:   /s/  Mikel D. Faulkner
      ----------------------
Name: Mikel D. Faulkner
Its:  President and CEO

Rodger Ehrlish (the Employee)

/s/ Rodger Ehrlish
------------------

Executive Severance Agreement--Johnston 3
Version 7/22/03

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