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                                                                    EXHIBIT 4(k)

                       ASSIGNMENT AND ASSUMPTION AGREEMENT
                           FOR THE GUARANTEE AGREEMENT

     This Assignment and Assumption Agreement (this "Agreement") is entered into
as of August 31, 2002 by and between CenterPoint Energy, Inc., a Texas
corporation (the "New Guarantor"), and Reliant Energy, Incorporated, a Texas
corporation (the "Existing Guarantor").

     WHEREAS, the Existing Guarantor and the Bank of New York, as Trustee (the
"Trustee"), are parties to the Guarantee Agreement (relating to REI Trust I)
dated as of February 26, 1999 (the "Guarantee") in favor of the Holders of, and
providing for the guaranty of, certain amounts relating to the 7.20% Trust
Originated Preferred Securities issued by REI Trust I, a Delaware statutory
business trust (the "Securities");

     WHEREAS, pursuant to an Agreement and Plan of Merger dated as of October
19, 2001, among the Existing Guarantor, the New Guarantor and Reliant Energy
MergerCo, Inc., a Texas corporation and an indirect wholly owned subsidiary of
the New Guarantor ("MergerCo"), MergerCo will be merged with and into the
Existing Guarantor (the "Merger"), with the Existing Guarantor to be the
surviving corporation, as a result of which, at the effective time of the Merger
each share of common stock, without par value, of the Existing Guarantor will be
converted into one share of the New Guarantor's common stock and the Existing
Guarantor will become a wholly owned subsidiary of the New Guarantor;

     WHEREAS, concurrently with the Merger, the Existing Guarantor will (i)
distribute the capital stock of all of its subsidiaries, other than certain
financing subsidiaries, to the New Guarantor (the "Stock Distribution") and (ii)
convey its Texas electric generation assets and certain buildings and related
assets to indirect wholly owned subsidiaries of the New Guarantor (the "Asset
Conveyance," and together with the Merger and the Stock Distribution, the
"Restructuring");

     WHEREAS, the Restructuring is a transfer of the Existing Guarantor's
properties and assets substantially as an entirety;

     WHEREAS, the sole asset of REI Trust I is an aggregate amount of junior
subordinated debentures (the "Debentures"), issued under the Junior Subordinated
Indenture dated as of February 15, 1999, as supplemented by Supplemental
Indenture No. 1 dated as of February 15, 1999 between the Existing Guarantor and
the Trustee (as supplemented, the "Indenture"), equal to the aggregate
liquidation amount of the Securities and the common securities issued by REI
Trust I;

     WHEREAS, as required by Section 10.01 of the Indenture, pursuant to
Supplemental Indenture No. 2 dated as of the date hereof, the New Guarantor is
assuming the

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obligations of the Existing Guarantor under the Debentures and the Indenture as
transferee of the Existing Guarantor's properties and assets substantially as an
entirety;

     WHEREAS, as contemplated by Section 9.01 of the Guarantee, the New
Guarantor is hereby assuming all obligations of the Existing Guarantor under the
Guarantee and for all purposes is becoming the "Guarantor" under the Guarantee;

     NOW, THEREFORE, in consideration of the foregoing, and for good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties agree as follows:

     1. Assignment. The Existing Guarantor hereby assigns and delegates to the
New Guarantor all of its rights and obligations under the Guarantee.

     2. Assumption. The New Guarantor hereby accepts the foregoing assignment by
the Existing Guarantor and hereby assumes all of the Existing Guarantor's rights
and obligations under the Guarantee.

     3. Substitution and Release. The New Guarantor unconditionally and
irrevocably (i) agrees to be substituted for the Existing Guarantor under the
Guarantee and for all purposes become the "Guarantor" under the Guarantee and
(ii) releases the Existing Guarantor from all liabilities and obligations under
the Guarantee.

     4. Miscellaneous. THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO THE
CONFLICTS OF LAW PRINCIPLES THEREOF. This Agreement shall inure to the benefit
of the Holders (as defined in the Guarantee) and their respective successors and
assigns, and is entered into by the New Guarantor for the express benefit of
such Holders and the Existing Guarantor.

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     IN WITNESS WHEREOF, the undersigned have caused this Agreement to be
executed by its duly authorized officer as of the date first above written.

                                       CENTERPOINT ENERGY, INC.

                                       By:           /s/ Rufus Scott
                                          --------------------------------------
                                          Name: Rufus Scott
                                                Title: Vice President

                                       RELIANT ENERGY, INCORPORATED

                                       By:          /s/ Marc Kilbride
                                          --------------------------------------
                                          Name: Marc Kilbride
                                          Title: Treasurer

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                                                                    EXHIBIT 4(l)

                       ASSIGNMENT AND ASSUMPTION AGREEMENT
                                     FOR THE
                    AGREEMENTS AS TO EXPENSES AND LIABILITIES
                                     AND THE
                      AMENDED AND RESTATED TRUST AGREEMENTS

     This Assignment and Assumption Agreement (this "Agreement") is entered into
as of August 31, 2002 by and between CenterPoint Energy, Inc., a Texas
corporation (the "New Obligor"), and Reliant Energy, Incorporated, a Texas
corporation (formerly Houston Lighting & Power Company) (the "Existing
Obligor").

     WHEREAS, (i) the Existing Obligor and HL&P Capital Trust I, a Delaware
business trust ("Trust I"), are parties to the Agreement as to Expenses and
Liabilities dated as of February 4, 1997 (the "Trust I Expense Agreement") in
favor of the beneficiaries of Trust I, providing for the guaranty of full
payment of certain obligations of Trust I in connection with Trust I's issuance
and sale of its 8.125% Trust Preferred Securities, Series A (the "Preferred
Securities"), and (ii) the Existing Obligor and HL&P Capital Trust II , a
Delaware business trust, ("Trust II") are parties to the Agreement as to
Expenses and Liabilities dated as of February 4, 1997 (the "Trust II Expense
Agreement," and together with the Trust I Expense Agreement, the "Expense
Agreements") in favor of the beneficiaries of Trust II, providing for the
guaranty of full payment of certain obligations of Trust II in connection with
Trust II's issuance and sale of its 8.257% Capital Securities, Series B (the
"Capital Securities, and together with the Preferred Securities, the
"Securities");

     WHEREAS, pursuant to an Agreement and Plan of Merger dated as of October
19, 2001, among the Existing Obligor, the New Obligor and Reliant Energy
MergerCo, Inc., a Texas corporation and an indirect wholly owned subsidiary of
the New Obligor ("MergerCo"), MergerCo will be merged with and into the Existing
Obligor (the "Merger"), with the Existing Obligor to be the surviving
corporation, as a result of which, at the effective time of the Merger each
share of common stock, without par value, of the Existing Obligor will be
converted into one share of the New Obligor's common stock, par value $0.01 per
share, and the Existing Obligor will become a wholly owned subsidiary of the New
Obligor;

     WHEREAS, concurrently with the Merger, the Existing Obligor will (i)
distribute the capital stock of all of its subsidiaries, other than certain
financing subsidiaries, to the New Obligor (the "Stock Distribution") and (ii)
convey its Texas electric generation assets and certain buildings and related
assets to indirect wholly owned subsidiaries of the New Obligor (the "Asset
Conveyance," and together with the Merger and the Stock Distribution, the
"Restructuring");

     WHEREAS, the Restructuring is a transfer of the Existing Obligor's
properties and assets substantially as an entirety;

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     WHEREAS, the sole asset of each of Trust I and Trust II is an aggregate
principal amount of junior subordinated debentures (the "Debentures"), issued
under the Junior Subordinated Indenture dated as of February 1, 1997 between the
Existing Obligor and The Bank of New York, as Trustee (the "Trustee"), as
supplemented by Supplemental Indenture No. 1 and Supplemental Indenture No. 2
both dated as of February 1, 1997 and both between the Existing Obligor and the
Trustee (as supplemented, the "Indenture"), equal to the aggregate liquidation
amount of the Securities and the common securities issued by each Trust;

     WHEREAS, as required by Section 8.1 of the Indenture, pursuant to
Supplemental Indenture No. 3 dated as of the date hereof, the New Obligor is
assuming the obligations of the Existing Obligor under the Debentures and the
Indenture as transferee of the Existing Obligor's properties and assets
substantially as an entirety and in connection therewith, the Existing Obligor
desires to transfer the Common Securities of each Trust to the New Obligor;

     WHEREAS, pursuant to Section 5.10 of each of Trust I's and Trust II's
Amended and Restated Trust Agreement, each dated as of February 4, 1997 and
among the Existing Obligor, as Depositor, the Trustee as Property Trustee and
The Bank of New York (Delaware) as Delaware Trustee (together, the "Trust
Agreements"), in order to transfer the Common Securities, the Existing Obligor
must transfer and the New Obligor must assume all rights and obligations under
the Expense Agreements;

     WHEREAS, as contemplated by Section 2.1 of each of the Expense Agreements,
the Existing Obligor is hereby assigning to the New Obligor and the New Obligor
is hereby assuming from the Existing Obligor, all obligations of the Existing
Obligor under the Expense Agreements and for all purposes is becoming the
"Corporation" under the Expense Agreements;

     WHEREAS, pursuant to Section 10.8 of each of the Trust Agreements, the
Existing Obligor may assign its obligations under the Trust Agreements in
connection with the Restructuring;

     WHEREAS, as contemplated by Section 10.8 in each of the Trust Agreements,
the Existing Obligor is hereby assigning to the New Obligor and the New Obligor
is hereby assuming from the Existing Obligor, all obligations of the Existing
Obligor under the Trust Agreements and for all purposes becoming the "Depositor"
under the Trust Agreements;

     NOW, THEREFORE, in consideration of the foregoing, and for good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties agree as follows:

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     1. Assignment. The Existing Obligor hereby assigns and delegates to the New
Obligor all of its rights and obligations under the Expense Agreements and under
the Trust Agreements.

     2. Assumption. The New Obligor hereby accepts the foregoing assignment by
the Existing Obligor and hereby assumes all of the Existing Obligor's rights and
obligations under the Expense Agreements and under the Trust Agreements.

     3. Release and Substitution. The New Obligor unconditionally and
irrevocably (i) releases the Existing Obligor from all obligations and
liabilities under the Expense Agreements and the Trust Agreements and (ii)
agrees to be substituted for the Existing Obligor under the Expense Agreements
and the Trust Agreements and for all purposes is becoming (x) the "Corporation"
under the Expense Agreements and (y) the "Depositor" under the Trust Agreements.

     4. Governing Law. THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO THE
CONFLICTS OF LAW PRINCIPLES THEREOF.

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     IN WITNESS WHEREOF, the undersigned have caused this Agreement to be
executed by its duly authorized officer as of the date first above written.

                                        CENTERPOINT ENERGY, INC.

                                        By:          /s/ Rufus Scott
                                           -------------------------------------
                                           Name: Rufus Scott
                                           Title:    Vice President

                                        RELIANT ENERGY, INCORPORATED

                                        By:         /s/ Marc Kilbride
                                           -------------------------------------
                                           Name: Marc Kilbride
                                           Title: Treasurer

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