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                                                                     Exhibit 2.4

                                   GLENCORE AG
                               Baarermattstrasse 3
                                  CH-6341, Baar
                                   SWITZERLAND

                               September 22, 2004

Kaiser Aluminum & Chemical Corporation
Suite 2500
5847 San Felipe
Houston, Texas  77057

Kaiser Alumina Australia Corporation
Suite 2500
5847 San Felipe
Houston, Texas  77057

             Re: Agreement to Submit Qualified Bid for QAL Interests

Gentlemen:

      We refer to the draft Purchase Agreement dated September 22, 2004
("Purchase Agreement") which is being entered into by and among Comalco
Aluminium Limited, a Queensland corporation ("CAL"), Kaiser Aluminum & Chemical
Corporation, a Delaware corporation ("KACC"), and Kaiser Alumina Australia
Corporation, a Delaware corporation ("Kaiser"), a copy of which is attached
hereto as Appendix A. We also refer to (i) the draft Expedited Motion of Debtors
and Debtors in Possession for (i) an Order Approving (a) Bidding Procedures for
the Sale of Their Interests in and Related to Queensland Alumina Limited and (b)
Certain Bid Protections with Respect to the Sale, and (ii) a Separate Order
Authorizing Them to (a) Enter Into Purchase Agreement, (b) Sell Their Interests
in and Related to Queensland Alumina Limited Free and Clear of Liens, Claims and
Encumbrances, and (c) Assume and Assign Related Executory Contracts (the
"Bidding Procedures Motion"), a copy of which is attached hereto as Appendix B;
and (ii) the draft Expedited Motion of Debtors and Debtors in Possession for an
Order (i) Approving the Entry Into an Overbid Agreement and (ii) Authorizing
Them to Pay a Threshold Qualified Bid Fee in Connection With the Sale of Their
Interests in and Related to Queensland Alumina Limited (the "Qualified Bid Fee
Motion"), a copy of which is attached hereto as Appendix C. Unless otherwise
indicated, all capitalized terms used but not defined in this letter shall have
the meanings ascribed to them in the Purchase Agreement, the Bidding Procedures
Motion or the Qualified Bid Fee Motion, as applicable.

      The undersigned acknowledges that KACC and Kaiser have informed the
undersigned that they are entering into the Purchase Agreement with CAL and will
file the Bidding Procedures Motion and the Qualified Bid Fee Motion together in
reliance upon the undersigned's

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execution, delivery and performance of this letter agreement ("Agreement"). The
undersigned confirms that it has completed its due diligence investigation with
respect to the QAL Interests and hereby agrees, on the terms and conditions
stated in this Agreement, to submit, through its indirectly wholly owned
subsidiary, Pegasus Queensland Acquisition Pty Limited ("Pegasus"), a Qualified
Bid to purchase the QAL Interests conforming to all requirements described in
the Bidding Procedures Motion and including a Base Share Price of US$400
million. Without limiting the generality of the foregoing agreement, the form of
Qualified Bidder Sale Documentation and related materials that shall be
submitted as part of the Qualified Bid described herein shall be (i) the mark-up
of the Purchase Agreement and the Exhibits and Schedules thereto attached hereto
as Appendix D; (ii) a copy of the agreement described in the immediately
preceding subclause executed by Pegasus; and (iii) an executed copy of the
certificate attached hereto as Appendix E, setting forth certain statements of
the undersigned relating to the Qualified Bid described herein. In addition to
the foregoing, simultaneously with the submission of such Qualified Bid, the
undersigned will make a deposit in the amount of $40,000,000 (the "Bid Deposit")
in accordance with the terms of the Bidding Procedures Motion and an escrow
agreement ("Escrow Agreement") to be entered into among Pegasus, KACC, Kaiser
and Wilmington Trust Company, as escrow agent (the "Escrow Agent"),
substantially in the form attached hereto as Appendix F.

      Kaiser and KACC hereby confirm that the delivery by the undersigned and
Pegasus respectively, of the documents described in the preceding paragraph,
together with the financial information previously provided to Lazard Freres &
Co. LLC ("Lazard"), will, upon payment of the Bid Deposit to the Escrow Agent,
constitute a Qualified Bid. Accordingly, the parties hereto acknowledge and
agree that Clause 1.2.1 of the Escrow Agreement is not applicable. Furthermore,
simultaneously with the execution and delivery of this Agreement, Lazard will
deliver to the undersigned a written notice confirming that the undersigned,
acting through Pegasus as described in this Agreement, is a Qualified Bidder.

      The undersigned hereby agrees to submit through Pegasus a Qualified Bid as
described in the second paragraph of this Agreement within two business days
after the Bankruptcy Court's entry of an order in the form annexed to Appendix C
approving the Qualified Bid Fee Motion (the "Qualified Bid Fee Order") and
simultaneously with the undersigned's receipt of the Qualified Bid Fee described
in the following paragraph; provided that the Qualified Bid Fee Order is entered
on or before October 15, 2004, or such later date as the parties agree. Such
Qualified Bid shall remain binding for the period of time specified in the
Bidding Procedures. Kaiser and KACC agree to use their respective commercially
reasonable best efforts such that the Bankruptcy Court hearing on the Bidding
Procedures Motion and the Qualified Bid Fee Motion occurs on September 27, 2004,
or if not on such date, in any event on the first available Bankruptcy Court
hearing date that occurs on or before October 15, 2004, if any. Furthermore,
Kaiser and KACC agree not to amend the Bidding Procedures as set forth in the
Bidding Procedures Motion prior to the entry of the Bankruptcy Court order
approving such motion.

      In consideration of the undersigned's agreement to submit through Pegasus
a Qualified Bid as described in the second paragraph of this Agreement, Kaiser
and KACC shall, subject to the Bankruptcy Court's entry of the Qualified Bid Fee
Order, jointly and severally pay or cause the payment to the undersigned of the
Qualified Bid Fee in the amount of US$7,680,000 (plus any Australian goods and
services tax legally required to be paid) within two business days after

                                      -2-
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the Bankruptcy Court's entry of the Qualified Bid Fee Order. The Qualified Bid
Fee shall be deemed earned by the undersigned immediately upon submission of the
Qualified Bid, shall be final and non-refundable, and shall not be subject to
avoidance for any reason whatsoever.

      For the avoidance of doubt, the parties acknowledge that the effectiveness
of this Agreement is subject to the Bankruptcy Court's timely entry of the
Qualified Bid Fee Order. If the Bankruptcy Court does not timely enter the
Qualified Bid Fee Order, Kaiser and KACC shall not be obligated to pay the
Qualified Bid Fee and the undersigned shall not be obligated to submit through
Pegasus a Qualified Bid as described herein, although the undersigned, Pegasus
or any of their respective affiliates shall have the right to do so.

      The undersigned acknowledges that Kaiser and KACC are entering into the
Purchase Agreement with CAL in reliance upon the undersigned's agreement to
submit through Pegasus a Qualified Bid for the QAL Interests as described in the
second paragraph of this Agreement. Accordingly, if the Qualified Bid Fee Order
is timely entered and the undersigned fails to submit such Qualified Bid, the
undersigned agrees that the sole quantum of damages that will be suffered by
Kaiser and KACC is equal to US$400 million less the higher of (i) the Base Share
Price stated in the Purchase Agreement with CAL and (ii) the Base Share Price
contained in any Successful Bid that is approved by the Bankruptcy Court
following the Auction.

      Finally, we refer to the letter agreement among Kaiser, KACC, Comalco
Limited and Rio Tinto Limited, a copy of which is attached as Exhibit B to the
Bidding Procedures Motion. The undersigned agrees to cooperate with Kaiser and
KACC to enable Kaiser and KACC to timely provide to CAL and Comalco such
information relating to the undersigned and Pegasus as may be reasonably
required for the purposes stated in the penultimate paragraph of such letter
agreement.

      The parties agree that the governing law of this Agreement is the internal
law of the State of New York, USA, without regard to principles of conflict of
laws, and submit to the jurisdiction of the courts as set forth in Appendix G in
any dispute arising out of or related to the transactions contemplated by this
Agreement.

      If the foregoing accurately sets forth your understanding of the agreement
between us, please so indicate by signing below.

                                          Sincerely,

                                          Glencore AG

                                          By: /s/ Steven J. Rejsman
                                              ---------------------------------
                                               Name: Steven J. Rejsman
                                               Title:   Authorized Signatory

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ACKNOWLEDGED AND AGREED:

Kaiser Aluminum & Chemical Corporation

By: /s/ Edward F. Houff
    -----------------------------------
    Name:  Edward F. Houff
    Title: Vice President

Kaiser Alumina Australia Corporation

By: /s/ Edward F. Houff
    -----------------------------------
    Name:  Edward F. Houff
    Title: Vice President

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                                   Appendix A

                           Comalco Purchase Agreement

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                                   Appendix B

                            Bidding Procedures Motion

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                                   Appendix C

                            Qualified Bid Fee Motion

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                                   Appendix D

                       Qualified Bidder Sale Documentation

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                                   Appendix E

                           Qualified Bid Certification

      Reference is hereby made to the Expedited Motion of Debtors and Debtors in
Possession for (i) an Order Approving (a) Bidding Procedures for the Sale of
Their Interests in and Related to Queensland Alumina Limited and (b) Certain Bid
Protections with respect to the Sale, and (ii) a Separate Order Authorizing Them
to (a) Enter Into Purchase Agreement, (b) Sell Their Interests in and Related to
Queensland Alumina Limited Free and Clear of Liens, Claims and Encumbrances, and
(c) Assume and Assign Related Executory Contracts (the "Bidding Procedures
Motion"), filed by the Debtors (as such term is defined in the Bidding
Procedures Motion) with the United States Bankruptcy Court for the District of
Delaware on September 22, 2004. Capitalized terms used but not defined herein
shall have the meanings ascribed to them in the Bidding Procedures Motion.

      In connection with the submission by the undersigned, through its
indirectly wholly owned subsidiary, Pegasus Queensland Acquisition Pty Limited
("Pegasus") of a Qualified Bid to purchase the QAL Interests in accordance with
the procedures set forth in the Bidding Procedures Motion, the undersigned
hereby certifies that:

1.    The undersigned is prepared to cause Pegasus to enter into the transaction
      immediately upon completion of the Auction if the undersigned is the
      Successful Bidder by executing a revised Qualified Bidder Agreement (to
      the extent necessary if the Qualified Bidder Agreement is modified at the
      Auction) and consummating the transaction not later than 150 days
      following the entry of the Sale Approval Order.

2.    The Qualified Bidder Sale Documentation submitted by the undersigned as
      part of its Qualified Bid shall remain binding during the applicable
      period described in "Return of Deposits" in the Bidding Procedures Motion.

3.    Except for the letter agreement dated September 22, 2004 among the
      undersigned and the Sellers, there are no arrangements between the
      undersigned or any of its affiliates, on the one hand, and any
      unaffiliated third parties, including affiliates of Sellers, relating to
      the undersigned's Qualified Bid, or to participation by such third parties
      in the Auction, or to ownership or operation of the Assets Sold, such as
      joint venture agreements, with other potential bidders (except for the
      agreements and contracts described in the definition of Assumed Interests
      and Obligations).

4.    Notwithstanding that the entity submitting the Qualified Bidder
      Documentation with respect to the Qualified Bid is Pegasus, the
      undersigned is financially responsible for such Qualified Bid and
      guarantees performance by Pegasus of the terms thereof.

Dated as of ______________, 2004.              Glencore AG

                                               By:_____________________________
                                                  Name:
                                                  Title:

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                                   Appendix F

                         Form of Bidder Escrow Agreement

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                                   Appendix G

                           Submission to Jurisdiction

      (a) The Bankruptcy Court will have jurisdiction over any dispute arising
out of or related to the transactions contemplated by this Agreement through the
date of entry of the order approving the final decree in the later of the
Bankruptcy Cases of Kaiser of KACC to be resolved. The parties to this Agreement
consent to the exclusive jurisdiction of the Bankruptcy Court (and of the
appropriate appellate courts therefrom) in any such dispute or action related
thereto, and irrevocably waive, to the fullest extent permitted by applicable
legislation, any objection that they may now or hereafter have to the laying of
the venue of any such dispute in the Bankruptcy Court or that any such dispute
brought in the Bankruptcy Court has been brought in an inconvenient forum.

      (b) Subject to the consent to the jurisdiction of the Bankruptcy Court
described in Clause (a), each of the parties to this Agreement irrevocably
submits to the non-exclusive jurisdiction of the United States District Court
for the Southern District of the State of New York, or if such court refuses to
accept or does not have subject matter jurisdiction, then to the Supreme Court
of the State of New York sitting in the County of New York, and the appellate
courts having jurisdiction of appeals from such courts, over any dispute arising
out of or relating to this Agreement or any of the transactions contemplated
thereby (but not in respect of any other matter) and each of the parties to this
Agreement hereby irrevocably agrees that (without prejudice to the jurisdiction
of any other court) all claims in respect of such dispute or any action related
thereto may be heard and determined in such courts. The parties to this
Agreement hereby irrevocably waive, to the fullest extent permitted by
applicable law, any objection which they may now or hereafter have to the laying
of venue of any such dispute brought in such court or any defense of
inconvenient forum for the maintenance of such dispute. Each of the parties to
this Agreement agrees that a judgment in any such dispute may be enforced in
other jurisdictions by suit on the judgment or in any other manner provided by
applicable law.