EXHIBIT 10.20

                                April 28, 1997

Cheniere Energy Operating Company, Inc.
237 Park Avenue, Suite 2100
New York, NY 10017

                                Re: Fifth Amendment to Exploration Agreement 
                                    dated April 4, 1996 between Zydeco 
                                    Exploration, Inc. and FX Energy, Inc.

Gentlemen:

In accordance with the provisions of Section 16.b of the captioned Agreement and
when accepted by you in the manner hereinafter provided, this letter shall 
constitute our agreement to amend said document to provide for expansion of the 
Area of Mutual Interest as stipulated in Section 14 thereof and depicted on 
Exhibit "B" attached thereto as follows, to wit:

     The Area of Mutual Interest is hereby expanded to include those Blocks
     within the area of 3-D seismic coverage acquired by Zydeco Exploration,
     Inc. from Fairfield Industries Inc. by Supplement Agreement No. 1 to Master
     License Agreement dated January 9, 1997, lying or being situated outside of
     the existing AMI, and being Blocks 24, 25, 40, 41, 42, 43, 44, and 45, West
     Cameron Area, Offshore Louisiana.

Except as herein specifically amended, all other provisions of the captioned 
Agreement shall remain unchanged. If you are in agreement with the foregoing, 
please so indicate by signing and returning the attached copy of this letter for
completion of our files.

                                             Very truly yours,

                                             /s/ John O. Smith

                                             John O. Smith
                                             President & Chief Operating Officer

ACCEPTED AND AGREED TO
THIS 28 DAY OF APRIL, 1997.

CHENIERE ENERGY OPERATING COMPANY, INC.

/s/ Walter Williams
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    Walter Williams
    Vice Chairman