Document:

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                                                                   Exhibit 10.37

CHENIERE ENERGY, INC.

                                                   TWO ALLEN CENTER
                                                   1200 SMITH STREET, SUITE 1740
                                                   HOUSTON, TEXAS  77002-4312
                                                   (713) 659-1361
                                                   FAX: (713) 659-5459

                                October 13, 1999

Lender

     Form of Ninth Amendment to Securities Purchase Agreement ("Ninth
Amendment")

Dear Lender:

     Reference is made to the Securities Purchase Agreement dated as of
December 15, 1997 as amended by the Third Amendment dated on or about
September 13, 1998, by the Fourth Amendment dated January 12, 1999 and by the
Fifth Amendment dated March 15, 1999, by the Sixth Amendment dated April 14,
1999, by the Seventh Amendment dated May 19, 1999 and by the Eighth Amendment
dated July 13, 1999 (as amended, the "Agreement"), between Cheniere Energy,
Inc., a Delaware corporation ("Borrower"), and Lender. Unless otherwise
indicated, all capitalized terms herein are used as defined in the Agreement.

     Cheniere is presently undertaking to raise $12,000,000 through a private
placement of convertible preferred stock in which San Jacinto Securities is
acting as the financial advisor.  It is expected that this preferred stock
offering will close by the end of October.  In addition, we have engaged RP&C
International to assist in a European private placement of $20,000,000 in
convertible notes payable, which private placement will be initiated later this
month and is expected to close in November.  Repayment of the amounts due to
Lender will be made from the proceeds of these offerings, and will be occur as
soon as practicable after the closing of the first offering.

     The purpose of this amendment to the Agreement is to extend the maturity
date from October 15, 1999 to December 15, 1999 as described below.

     For good and valuable consideration, consisting of 10 percent of the
outstanding balance of your note, payable in Cheniere common stock valued at
$1.20 per share, the receipt and adequacy of which are hereby acknowledged,
Borrower and Lender agree as follows:

     1. Amendment of Maturity Date.  The definition of Maturity Date in Section
        12 shall be hereby amended by replacing the paragraph captioned MATURITY
        DATE in its entirety with the following paragraph:
<PAGE>

               "MATURITY DATE means the earlier of (a) December 15, 1999 and (b)
          the date that the Senior Notes are declared immediately due and
          payable pursuant to SECTION 11 in the event of a Default; provided
          that Lender's rights continue until the Obligation has been paid and
          performed in full."

     2. Representations and Warranties.  Borrower represents and warrants that
        it possesses all requisite power and authority to execute, deliver and
        comply with the terms of this instrument, which has been duly authorized
        and approved by all necessary corporate action and for which no consent
        of any person is required.

     3. Fees and Expenses.  Borrower agrees to pay the reasonable fees and
        expenses of counsel to Lender for services rendered in connection with
        the negotiation and execution of this instrument.

     4. Loan Paper; Effect.  This instrument is a Loan Paper and, therefore, is
        subject to the applicable provisions of Section 13 of the Agreement, all
        of which are incorporated herein by reference the same as if set forth
        herein verbatim.  In the event of any inconsistency between the terms of
        the Agreement as hereby modified (the "Amended Agreement") and any other
        Loan Papers, the terms of the Amended Agreement shall control and such
        other document shall be deemed to be amended hereby to conform to the
        terms of the Amended Agreement.

     5. No Waiver of Defaults.  This instrument does not constitute a waiver of,
        or a consent to any present or future violation of or default under, any
        provision of the Loan Papers, or a waiver of Lender's right to insist
        upon future compliance with each term, covenant, condition and provision
        of the Loan Papers, and the Loan Papers shall continue to be binding
        upon, and inure to the benefit of, Borrower, Lender and their respective
        successors and assigns.

     8. Final Agreement. THE LOAN PAPERS, AS AMENDED HEREBY, REPRESENT THE FINAL
        AGREEMENT BETWEEN THE PARTIES AND MAY NOT BE CONTRADICTED BY EVIDENCE OF
        PRIOR, CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES.
        THERE ARE NO ORAL AGREEMENTS BETWEEN THE PARTIES.

     If the foregoing terms and conditions are acceptable to Lender, Lender
should indicate its acceptance by signing in the space provided below and
returning an executed copy hereof to Borrower, whereupon this letter shall
become an agreement binding upon and inuring to the benefit of Borrower and
Lender and their respective successors and assigns.

                                      Sincerely,

                                      CHENIERE ENERGY, INC.

                                      By:
                                         -------------------------------
                                         Don A. Turkleson
                                         Chief Financial Officer
Accepted and agreed to as of the day
and year first set forth in this Ninth
Amendment.

------------------------------
Lender

                                       2<PAGE>

                                                                   Exhibit 10.38

CHENIERE ENERGY, INC.

                                                   TWO ALLEN CENTER
                                                   1200 SMITH STREET, SUITE 1740
                                                   HOUSTON, TEXAS  77002-4312
                                                   (713) 659-1361
                                                   FAX: (713) 659-5459

                               December 13, 1999
Lender

     Form of Tenth Amendment to Securities Purchase Agreement ("Ninth
Amendment")

Dear Lender:

     Reference is made to the Securities Purchase Agreement dated as of
December 15, 1997 as amended by the Third Amendment dated on or about
September 13, 1998, by the Fourth Amendment dated January 12, 1999 and by the
Fifth Amendment dated March 15, 1999, by the Sixth Amendment dated April 14,
1999, by the Seventh Amendment dated May 19, 1999, by the Eighth Amendment dated
July 13, 1999, by letter agreement dated August 25, 1999 and by the Ninth
Amendment dated October 13, 1999 (as amended, the "Agreement"), between Cheniere
Energy, Inc., a Delaware corporation ("Borrower"), and Lender. Unless otherwise
indicated, all capitalized terms herein are used as defined in the Agreement.

     The purposes of this amendment to the Agreement are to extend the maturity
date from December 15, 1999 to March 15, 2000 and to increase from $12,000,000
to $16,000,000 the amount of net funds which Borrower may raise through private
placement of its equity securities or from the sale of seismic data and retain
for use in its business before being required to direct the proceeds from such
sources to prepayment of the Term Loan.

     For good and valuable consideration, which includes the issuance of 12,971
shares of Cheniere Energy, Inc. common stock, the issuance of three-year
warrants to purchase 89,227 shares of Cheniere common stock and the adjustment
of the exercise price to a dollar amount yet to be determined, but which will
fall within the range of $0.75 to $1.00 per share, for all outstanding warrants
issued pursuant to the Agreement, the receipt and adequacy of which are hereby
acknowledged, Borrower and Lender agree as follows:

     2. Amendment of Terms of Payment. Section 2 of the Agreement is hereby
        amended by replacing paragraph (c) of such Section in its entirety with
        the following paragraph:

             (c) "In addition to prepayments under clause (b) above, Borrower
        shall make prepayments of principal of the Term Loan equal to the net
        cash proceeds received by Borrower from any private placement of
        Borrower's equity securities or from any sale by Borrower of seismic
        data, less up to $16,000,000 which may be retained by Borrower."
<PAGE>

     2. Amendment of Maturity Date.  The definition of Maturity Date in Section
        12 shall be hereby amended by replacing the paragraph captioned MATURITY
        DATE in its entirety with the following paragraph:

               "MATURITY DATE means the earlier of (a) March 15, 2000 and (b)
          the date that the Senior Notes are declared immediately due and
          payable pursuant to SECTION 11 in the event of a Default; provided
          that Lender's rights continue until the Obligation has been paid and
          performed in full."

     3. Representations and Warranties.  Borrower represents and warrants that
        it possesses all requisite power and authority to execute, deliver and
        comply with the terms of this instrument, which has been duly authorized
        and approved by all necessary corporate action and for which no consent
        of any person is required.

     4. Fees and Expenses.  Borrower agrees to pay the reasonable fees and
        expenses of counsel to Lender for services rendered in connection with
        the negotiation and execution of this instrument.

     5. Loan Paper; Effect.  This instrument is a Loan Paper and, therefore, is
        subject to the applicable provisions of Section 13 of the Agreement, all
        of which are incorporated herein by reference the same as if set forth
        herein verbatim.  In the event of any inconsistency between the terms of
        the Agreement as hereby modified (the "Amended Agreement") and any other
        Loan Papers, the terms of the Amended Agreement shall control and such
        other document shall be deemed to be amended hereby to conform to the
        terms of the Amended Agreement.

     6. No Waiver of Defaults. This instrument does not constitute a waiver of,
        or a consent to any present or future violation of or default under, any
        provision of the Loan Papers, or a waiver of Lender's right to insist
        upon future compliance with each term, covenant, condition and provision
        of the Loan Papers, and the Loan Papers shall continue to be binding
        upon, and inure to the benefit of, Borrower, Lender and their respective
        successors and assigns.

     7. Final Agreement. THE LOAN PAPERS, AS AMENDED HEREBY, REPRESENT THE FINAL
        AGREEMENT BETWEEN THE PARTIES AND MAY NOT BE CONTRADICTED BY EVIDENCE OF
        PRIOR, CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES.
        THERE ARE NO ORAL AGREEMENTS BETWEEN THE PARTIES.

     If the foregoing terms and conditions are acceptable to Lender, Lender
should indicate its acceptance by signing in the space provided below and
returning an executed copy hereof to Borrower, whereupon this letter shall
become an agreement binding upon and inuring to the benefit of Borrower and
Lender and their respective successors and assigns.

                                      Sincerely,

                                      CHENIERE ENERGY, INC.

                                      By:
                                         ------------------------------
                                         Don A. Turkleson
                                         Chief Financial Officer
Accepted and agreed to as of the day
and year first set forth in this Tenth
Amendment.

--------------------------------
Lender

                                       2

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