Sabine Pass LNG 10-Q 2013 Q1 Quarterly report

Exhibit 32.1

CERTIFICATION BY CHIEF EXECUTIVE OFFICER

PURSUANT TO 18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the quarterly report of Sabine Pass LNG, L.P. (the “Partnership”) on Form 10-Q for the period ended March 31, 2013 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Charif Souki, Chief Executive Officer of Sabine Pass LNG-GP, LLC, the general partner of the Partnership, certify, pursuant to 18 U.S.C. § 1350, as adopted pursuant to § 906 of the Sarbanes-Oxley Act of 2002, to my knowledge, that:

(1) The Report fully complies with the requirements of section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

(2) The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Partnership.

/s/    CHARIF SOUKI

Charif Souki

Chief Executive Officer of Sabine Pass LNG-GP, LLC,

general partner of Sabine Pass LNG, L.P.

Date: May 3, 2013