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                                                                   EXHIBIT 10.43

                              ASSIGNMENT AGREEMENT

         This Assignment Agreement dated March 26, 2003 by and among Arnos Corp.
("Arnos" or "Lender"), Edgemont Limited Partnership ("Edgemont LP"), NEG
Operating LLC ("Operating LLC") and National Energy Group, Inc. ("NEG" or
"Assignor") shall act to assign that certain Loan Agreement dated August 29,
1996 among NEG as Borrower, NEG-OK Inc. and Boomer Marketing Corporation as
Guarantors AND Bank One Texas, N.A. and Credit Lyonnais, New York Branch, as
amended on October 31, 1996, March 7, 1997, May 12, 1997, August 21, 1997,
August 1, 2001 and December 15, 2001 (the "Loan Agreement"). Edgemont LP and
Operating LLC may sometimes be referred to herein collectively as "Assignees"
and individually as "Assignee".

                                   WITNESSETH:

         WHEREAS, pursuant to that certain Assignment Agreement between Bank One
Texas, N.A., Credit Lyonnais, New York Branch, and Arnos Corp. dated December
22, 1998, Arnos became successor-in-interest and acquired all of the right,
title and interest in and to the Loan Agreement held by Bank One Texas, N.A. and
Credit Lyonnais, New York Branch; and

         WHEREAS, Arnos, NEG, Edgemont LP and Operating LLC have agreed that all
of NEG's right, title and interest in and to the Loan Agreement shall be
assigned to Assignees.

         NOW THEREFORE, for good and valuable consideration, the sufficiency of
which is hereby acknowledged, the parties hereto agree as follows:

         1. Assignor hereby assigns and transfers to Assignees, and Assignees
hereby assume from Assignor all of Assignor's right, title and interest in and
to the Loan Agreement.

         2. Assignor hereby represents and warrants that it has the full right,
power and authority to transfer and assign its interest in the Loan Agreement,
subject to the consent of holders of NEG's senior note obligations.

         3. Each Assignee hereby represents and warrants that it has the full
right, power and authority to enter into and perform the obligations pursuant to
this Assignment Agreement and the Loan Agreement.

         4. This Assignment Agreement is effective of the date first written
above, and each Assignee is hereby deemed a party to the Loan Agreement with all
the rights and obligations of a Borrower thereunder. As of the effective date,
Assignor hereby relinquishes all its rights under the Loan Agreement and is
hereby released from any and all of its obligations pursuant thereto.

         5. Each of Lender, Assignor and Assignees shall take such action and
execute and deliver to the other all such documents and instruments as may be
necessary to implement this Assignment Agreement and to consummate the
transactions contemplated hereby.

         6. By its execution and delivery of this Assignment Agreement, each of
Arnos, NEG, Edgemont LP and Operating LLC (i) agrees to the assignment of the
Loan Agreement as contemplated herein, and (ii) waives compliance with Section
27(a)(1), (2) and (4) of the Loan Agreement.

         7. By its execution and delivery of this Assignment Agreement, each of
Arnos, High River Limited Partnership and High Coast Limited Partnership, as the
holders of NEG's senior note obligations, hereby consents to the assignment of
the Loan Agreement as contemplated herein.

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         8. THIS ASSIGNMENT AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO THE
PRINCIPALS OF CONFLICT OF LAWS.

         IN WITNESS WHEREOF, the parties have caused this Assignment Agreement
to be executed and delivered on the date first written above.

                                  Arnos Corp., as Lender and a Noteholder

                                  By: /s/ EDWARD E. MATTNER
                                     ------------------------------------------
                                  Name: Edward E. Mattner
                                  Its:  Vice President

                                  National Energy Group, Inc., as Assignor

                                  By: /s/ BOB G. ALEXANDER
                                     ------------------------------------------
                                  Name:  Bob G. Alexander
                                  Its:   President & Chief Executive Officer

                                  NEG Operating LLC, as Assignee
                                  By: NEG Holding LLC, Sole Member
                                  By: Gascon Partners, Managing Member
                                  By: Cigas Corp., Managing General Member

                                  By: /s/ EDWARD E. MATTNER
                                     ------------------------------------------
                                  Name: Edward E. Mattner
                                  Its:  President

                                  Edgemont Limited Partnership, as Assignee
                                  By: GP of Delaware LLC, its General Partner

                                  By: /s/ EDWARD E. MATTNER
                                     ------------------------------------------
                                  Name: Edward E. Mattner
                                  Its:  Manager

          CONSENTED TO BY NOTEHOLDERS:

          High River Limited Partnership
          By:  Barberry Corp., Its General Partner

          By: /s/ EDWARD E. MATTNER
             --------------------------------------------
          Name: Edward E. Mattner
          Its:  Authorized Signatory

          High Coast Limited Partnership
          By:  Beckton Corp. its General Partner

          By: /s/ EDWARD E. MATTNER
             --------------------------------------------
          Name: Edward E. Mattner
          Its:  Authorized Signatory<PAGE>
                                                                   EXHIBIT 10.44

                  SEVENTH AMENDMENT TO RESTATED LOAN AGREEMENT

          THIS SEVENTH AMENDMENT TO RESTATED LOAN AGREEMENT (hereinafter
referred to as the "Amendment") executed and effective as of the 26th day of
March 2003, by and among NATIONAL ENERGY GROUP, INC., a Delaware corporation
("Borrower"), and ARNOS CORP., a Nevada corporation ("Lender"), a successor by
assignment to BANK ONE, TEXAS, N.A., a national banking association ("Bank One")
and CREDIT LYONNAIS NEW YORK BRANCH ("Credit Lyonnais") and each of the
financial institutions which may from time to time become a party hereto or any
successor or assignee thereof (hereinafter collectively referred to as "Banks",
individually as "Bank").

                                   WITNESSETH:

          WHEREAS, Borrower, Guarantor, Banks and Agent entered into a Restated
Loan Agreement, dated as of August 29, 1996 (as so modified and amended and as
otherwise supplemented from time to time, the "Loan Agreement") under the terms
of which the Banks agreed to provide the Borrower with a reducing revolving line
of credit facility in an amount of up to $100,000,000 and a term loan in an
amount of up to $5,000,000;

          WHEREAS, Borrower, Guarantor, Banks, Agent and Lender, respectively,
have entered into a First Amendment to Restated Loan Agreement dated October 31,
1996, a Second Amendment to Restated Loan Agreement dated March 7, 1997, a Third
Amendment to Restated Loan Agreement dated May 12, 1997, a Fourth Amendment to
Restated Loan Agreement dated August 21, 1997, a Fifth Amendment to Restated
Loan Agreement dated August 1, 2001, and a Sixth Amendment to Restated Loan
Agreement dated December 15, 2001;

          WHEREAS, Borrower has assigned all of its right, title and interest in
and to the Loan Agreement to Edgemont LP, a Delaware limited partnership, and
NEG Operating LLC, a Delaware limited liability company (each of Edgemont LP and
NEG Operating LLC individually referred to herein as "Assignee Borrower" and
collectively as "Assignee Borrowers") effective March 26, 2003; and

          WHEREAS, Assignee Borrowers and Lender have agreed that certain
amendments be made to the Loan Agreement with respect to (i) the Revolving
Maturity Date, (ii) an increase in the Revolving Commitment, and (iii) an
increase in the Borrowing Base.

          NOW THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, each Assignee Borrower and the
Lender hereby agree as follows:

1. Definition

          Capitalized terms used and not otherwise defined herein shall have the
respective meanings ascribed thereto in the Loan Agreement.

2. Amendment to the Loan Agreement.

          The Loan Agreement is hereby amended as follows:

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         A. The definition of "Revolving Maturity Date" as defined in Section 1
shall be amended by deleting therefrom the date "August 29, 2000" and, in lieu
thereof, inserting the date "June 30, 2004;"

          B. The definition of "Revolving Commitment" as defined in Section 1
shall be amended by deleting in the first line therefrom the amount of
"$100,000,000" and, in lieu thereof, inserting the amount of "$150,000,000;" and

          C. The Borrowing Base as defined in Section 7 shall be deleted in its
entirety and amended as follows: "During the period from the date hereof to the
first Determination Date (as hereinafter defined), the Borrowing Base for the
Revolving Loan shall be $75,000,000 and the Monthly Commitment Reduction shall
be $0 per month beginning March 26, 2003."

3. Governing Law.

          This amendment shall be governed by the construed in accordance with
the laws of the State of New York, without regard to principles of conflicts of
law or choice of law.

4. Modification.

          No provisions of this Amendment may be waived, amended or modified
except in writing signed by the affected party.

5. Continued Effectiveness of the Loan Agreement; No Default or Event of
Default.

          Except as expressly provided herein, the terms and provisions of the
Loan Agreement shall remain unchanged and in full force and effect and all
references therein to this "Agreement" shall be deemed to be references to the
Loan Agreement, as amended by this Seventh Amendment and any preceding
amendments thereto. As of the date hereof, no Default or Event of Default has
occurred and is continuing under the Loan Agreement.

6.        Counterparts; Effective Date.

          This Amendment may be signed in one or more counterparts, all of which
together shall constitute a single agreement binding upon the parties hereto.
This Amendment shall be effective as of March 26, 2003.

                            [Signature Page Follows]

                                       2
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          IN WITNESS WHEREOF, parties hereto have caused this Amendment to be
executed by their duly authorized officers as of the date first written above.

                                  ARNOS CORP., as Lender

                                  By: /s/ EDWARD E. MATTNER
                                     ------------------------------------------
                                  Name: Edward E. Mattner
                                  Its:  Vice President

                                  NEG Operating LLC, as Assignee Borrower
                                  By: NEG Holding LLC, Sole Member
                                  By: Gascon Partners, Managing Member
                                  By: Cigas Corp., Managing General Member

                                  By: /s/ EDWARD E. MATTNER
                                     ------------------------------------------
                                  Name: Edward E. Mattner
                                  Its:  President

                                  Edgemont Limited Partnership, as Assignee
                                  By: GP of Delaware. LLC, its General Partner

                                  By: /s/ EDWARD E. MATTNER
                                     ------------------------------------------
                                  Name: Edward E. Mattner
                                  Its:  Manager

          CONSENTED TO BY NOTEHOLDERS:

          Arnos Corp.

          By: /s/ EDWARD E. MATTNER
             --------------------------------------------
          Name: Edward E. Mattner
          Its:  Vice President

          High River Limited Partnership
          By:  Barberry Corp., its General Partner

          By: /s/ EDWARD E. MATTNER
             --------------------------------------------
          Name: Edward E. Mattner
          Its:  Authorized Signatory

          High Coast Limited Partnership
          By:  Beckton Corp., its General Partner

          By: /s/ EDWARD E. MATTNER
             --------------------------------------------
          Name: Edward E. Mattner
          Its:  Authorized Signatory

        [Signature Page to Seventh Amendment to Restated Loan Agreement]

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