UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549

                                    FORM 8-K

                             CURRENT REPORT PURSUANT
                          TO SECTION 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

         Date of report (Date of earliest event reported) June 10, 2005

                              WILLBROS GROUP, INC.
             (Exact Name of Registrant as Specified in Its Charter)

                               Republic of Panama
                 (State or Other Jurisdiction of Incorporation)

                 1-11953                              98-0160660
        (Commission File Number)           (IRS Employer Identification No.)

                  Plaza 2000 Building, 50th Street, 8th Floor,
                P.O. Box 0816-01098, Panama, Republic of Panama
       (Address of Principal Executive Offices)           (Zip Code)

                                 (507) 213-0947
             (Registrant's Telephone Number, Including Area Code)

                                 Not Applicable
        (Former Name or Former Address, if Changed Since Last Report)

   Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions (see General Instruction A.2. below):

   [ ] Written communications pursuant to Rule 425 under the Securities Act (17
       CFR 230.425)

   [ ] Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17
       CFR 240.14a-12)

   [ ] Pre-commencement communications pursuant to Rule 14d-2(b) under the
       Exchange Act (17 CFR 240.14d-2(b))

   [ ] Pre-commencement communications pursuant to Rule 13e-4(c) under the
       Exchange Act (17 CFR 240.13e-4(c))

ITEM 2.04. TRIGGERING EVENTS THAT ACCELERATE OR INCREASE A DIRECT FINANCIAL
           OBLIGATION OR AN OBLIGATION UNDER AN OFF-BALANCE SHEET ARRANGEMENT.

      On March 31, 2005, Willbros Group, Inc. (the "Company") issued a press
release announcing that it would delay the filing of its Annual Report on Form
10-K for the year ended December 31, 2004, due to the continuation of an
independent investigation relating to its international operations.

      Pursuant to the Indenture dated as of March 12, 2004 (the "Indenture"),
between the Company, as issuer, and JPMorgan Chase Bank, as trustee with respect
to the Company's $70.0 million of 2.75% Convertible Senior Notes due 2024 (the
"Notes"), the Company is required to provide the trustee with copies of all
annual and quarterly reports which it is required to file with the SEC pursuant
to Section 13 or 15(d) of the Securities Exchange Act of 1934, as amended,
within 15 calendar days after it files such annual and quarterly reports. The
Indenture provides that a failure by the Company to comply with this requirement
is not an "event of default" until either (i) the trustee notifies the Company
or (ii) the holders of at least 25% in aggregate principal amount of the Notes
outstanding notify both the Company and the trustee, in each case by certified
mail, of the failure to perform, and the Company does not observe or perform the
covenant for a period of 60 days after written notice of such failure is given
in accordance with the Indenture. If an event of default were to occur, the
trustee or the holders of at least 25% in aggregate principal amount of the
Notes then outstanding could declare all unpaid principal and accrued interest
on the Notes then outstanding to be immediately due and payable. Moreover, any
failure by the Company to perform or observe any covenant under the Indenture
which would entitle the noteholders or the trustee to accelerate the Notes,
would also constitute an event of default under the Company's senior credit
facility.

      The Company has received a letter dated June 10, 2005, from a law firm
representing Whitebox Advisor, Inc., which claims to be the holder of
$17,595,000, or approximately 25.1% of the Notes. In this letter, Whitebox
Advisor, Inc. asserts that, as a result of the Company's failure to timely file
with the SEC its 2004 Form 10-K and its Quarterly Report on Form 10-Q for the
quarter ended March 31, 2005, it is placing the Company on notice of an event of
default.

      The Company does not believe that it has failed to perform its obligations
under the Indenture. As discussed above, the Indenture provision referenced in
the letter specifically requires that the Company ensure delivery of copies of
its annual and quarterly reports to the trustee within 15 calendar days after
they are filed with the SEC. The Indenture provision does not require the
Company to file those reports within the deadlines set forth in the SEC's rules
and regulations. The Company will furnish to the trustee copies of its 2004
Annual Report on Form 10-K and its Quarterly Report on Form 10-Q for the quarter
ended March 31, 2005, within 15 days after it files such reports with the SEC.
The Company believes that such action will comply fully with the Indenture.

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                                   SIGNATURES

     Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.

                                       WILLBROS GROUP, INC.


Date: June 16, 2005                    By: /s/ Warren L. Williams 
                                           ---------------------------
                                           Warren L. Williams
                                           Senior Vice President, Chief
                                           Financial Officer and Treasurer





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