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                                                                    EXHIBIT 31.1


                                 CERTIFICATIONS

I, Fiona A. Robertson, certify that:

1.       I have reviewed this annual report on Form 20-F of Petsec Energy Ltd;

2.       Based on my knowledge, this annual report does not contain any untrue
         statement of a material fact or omit to state a material fact necessary
         to make the statements made, in light of the circumstances under which
         such statements were made, not misleading with respect to the period
         covered by this annual report;

3.       Based on my knowledge, the financial statements, and other financial
         information included in this annual report, fairly present in all
         material respects the financial condition, results of operations and
         cash flows of the registrant as of and for, the periods presented in
         this annual report;

4.       The registrant's other certifying officers and I are responsible for
         establishing and maintaining disclosure controls and procedures (as
         defined in Exchange Act Rules 13a-15e and 15d-15e) for the registrant
         and have:

         (a)      designed such disclosure controls and procedures, or caused
                  such disclosure controls and procedures to be designed under
                  our supervision, to ensure that material information relating
                  to the registrant, including its consolidated subsidiaries, is
                  made known to us by others within those entities, particularly
                  during the period in which this annual report is being
                  prepared;

         (b)      evaluated the effectiveness of the registrant's disclosure
                  controls and procedures and presented in this report our
                  conclusions about the effectiveness of the disclosure controls
                  and procedures, as of the end of the period covered by this
                  report based on such evaluation; and

         (c)      disclosed in this annual report any change in the registrant's
                  internal control over financial reporting that occurred during
                  period covered by the annual report that has materially
                  affected, or is reasonably likely to materially affect, the
                  registrant's internal control over financial reporting; and

5.       The registrant's other certifying officers and I have disclosed, based
         on our most recent evaluation of internal control over financial
         reporting, to the registrant's auditors and the audit committee of the
         registrant's board of directors (or persons performing the equivalent
         function):

         (a)      all significant deficiencies and material weaknesses in the
                  design or operation of internal control over financial
                  reporting which are reasonably likely to adversely affect the
                  registrant's ability to record, process, summarize and report
                  financial information; and

         (b)      any fraud, whether or not material, that involves management
                  or other employees who have a significant role in the
                  registrant's internal controls over financial reporting;


Date:  May 24, 2004

/s/ Fiona A. Robertson

Fiona A. Robertson
Chief Financial Officer