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                                                                    EXHIBIT 31.1

                                 CERTIFICATIONS

I, Patrick Gallagher, certify that:

1.  I have reviewed this Amendment No. 1 to Annual Report on Form 10-K/A of FLAG
    Telecom Group Limited;

2.  Based on my knowledge, this 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 report;

3.  Based on my knowledge, the financial statements, and other financial
    information included in this 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 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-14 and 15d-14) for the registrant and we 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 report is being prepared;

b)  evaluated the effectiveness of the registrant's disclosure controls 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 report any change in the registrant's internal control
    over financial reporting that occurred during the registrant's most recent
    fiscal quarter (the registrant's fourth fiscal quarter in the case of any
    annual report) that has materially affected, or is reasonably likely to
    materially affect, the registrant's internal control over financial
    reporting;

5.  The registrant's other certifying officers and I have disclosed, based on
    our most recent evaluation, to the registrant's auditors and the audit
    committee of 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 controls 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.

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Date: August 14, 2003                          /s/ Patrick Gallagher
                                               --------------------------------------------
                                               Name: Patrick Gallagher
                                               Title: Chief Executive Officer
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