Exhibit 10.4

AMENDMENT NO. FOUR-B TO CREDIT AGREEMENT

This AMENDMENT NO. FOUR-B TO CREDIT AGREEMENT (this “Amendment”) is entered into, as of April 28, 2009, by Cheniere Common Units Holding, LLC, a Delaware limited liability company (the “Borrower”), the Loan Parties, the Lenders and The Bank Of New York Mellon, as administrative agent (in such capacity and together with its successors, the “Administrative Agent”) and as collateral agent (in such capacity and together with its successors, the “Collateral Agent”). All capitalized terms used in this Amendment and not otherwise defined herein have the meanings ascribed to such terms in the Credit Agreement (as defined below).

Preliminary Statements

A. Borrower has entered into that certain Credit Agreement, dated as of August 15, 2008, by and among the Borrower, the Administrative Agent, certain affiliates of the Borrower signatory thereto and the Lenders from time to time party thereto (as amended by that certain First Amendment to Credit Agreement, dated as of September 15, 2008, Second Amendment to Credit Agreement, dated as of December 31, 2008, Third Amendment to Credit Agreement, dated as of April 3, 2009, Fourth Amendment to Credit Agreement, dated as of April 9, 2009, and Amendment No. Four-A to Credit Agreement, dated as of April 27, 2009, as further amended, restated, supplemented or otherwise modified from time to time, the “Credit Agreement”);

B. Borrower has notified the Administrative Agent, the Collateral Agent and the Lenders that it desires to amend the Credit Agreement in order to be permitted to repurchase certain notes issued pursuant to the CEI Indenture; and

C. Subject to certain conditions as set forth herein, the Administrative Agent, the Collateral Agent and the Required Lenders are willing to agree to such amendment relating to the Credit Agreement.

NOW THEREFORE, in consideration of the premises and the agreements, other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Borrower, the Loan Parties, the Administrative Agent, the Collateral Agent and the Required Lenders, hereby agree as follows:

“Four-B Amendment” shall mean that certain Amendment No. Four-B to Credit Agreement, dated as of April 28, 2009, among Borrower, certain affiliates of Borrower signatory thereto, the Administrative Agent, the Collateral Agent and the Required Lenders.

“Four-B Amendment Effective Date” shall mean the date of satisfaction of the conditions referred to in Section 4 of the Four-B Amendment.”

“(f) Investments in an amount not to exceed $13,525,000 made by CEI with respect to repurchasing certain of the notes issued pursuant to the CEI Indenture.”.

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Notwithstanding anything to the contrary in this Amendment, each Lender by delivering its signature page to this Amendment shall be deemed to have acknowledged receipt of and consented to and approved the Amendment and each other document required to be approved by any Agent or any Lender, as applicable, on the date such Lender delivers its signature to this Amendment and the Administrative Agent shall be entitled to rely on such confirmation.

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Signature Page to Amendment No. Four-B

Signature Page to Amendment No. Four-B

Signature Page to Amendment No. Four-B

Signature Page to Amendment No. Four-B

Signature Page to Amendment No. Four-B

Signature Page to Amendment No. Four-B

Signature Page to Amendment No. Four-B