Exhibit 99.1


                          [WILLBROS GROUP, INC. LOGO]


                                        CONTACT:    Michael W. Collier
NEWS RELEASE                                        Investor Relations Manager
                                                    Willbros USA, Inc.
                                                    (713) 403-8016

FOR IMMEDIATE RELEASE                               Jack Lascar / Partner
                                                    DRG&E
                                                    (713) 529-6600


                     WILLBROS COMMENCES CONSENT SOLICITATION
                           ON CONVERTIBLE SENIOR NOTES


         HOUSTON, TEXAS - SEPTEMBER 8, 2005 - Willbros Group, Inc. (NYSE: WG)
announced today that it is soliciting consents from the holders of its
outstanding 2.75% convertible senior notes due 2024 to amend certain provisions
in the indenture governing the notes. By consenting to the proposed amendments
to the indenture, holders of the notes will also be consenting to waive any
potential defaults that may have occurred before the proposed amendments become
effective, to rescind a purported notice of default that was delivered to
Willbros under the indenture and to clarify that for a period ending on the
nine-month anniversary of the date the proposed amendments become effective, no
default will occur if Willbros fails to timely file a periodic report with the
SEC. Approval of the proposed amendments and waiver requires the consent of the
holders of a majority in principal amount of the outstanding notes. The record
date for the solicitation is September 6, 2005.

         The proposed amendments provide that:

     o   the initial date on or after which Willbros may redeem all or any
         portion of the notes will change from March 15, 2011 to March 15, 2013;
         and

     o   in the event of a fundamental change involving a sale of Willbros in
         which at least 10 percent of the sales proceeds are paid in cash,
         Willbros will pay a

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         make-whole payment to the holders of the notes. The make-whole payment
         will consist of no more than the present value of two years of
         scheduled interest payments on the notes.

No separate cash fee is being paid to holders for delivering consents.

         Willbros previously announced that it would not be able to timely file
its annual report on Form 10-K for the year ended December 31, 2004 and its
quarterly reports for the periods ended March 31, 2005 and June 30, 2005, and
Willbros has not filed them to date. On June 10, 2005, Willbros received a
letter from a representative of Whitebox Advisors, LLC asserting that, as a
result of Willbros' failure to timely file with the SEC its 2004 Form 10-K and
Quarterly Report on Form 10-Q for the quarter ended March 31, 2005, Whitebox
Advisors was placing Willbros on notice of an event of default under the
indenture. Willbros has previously indicated that it does not believe that it
has failed to perform its obligation under the indenture.

         On August 19, 2005, Willbros reached an agreement with Whitebox
Advisors, the beneficial owner of approximately 25.1% of the notes as of June
10, 2005, pursuant to which it agreed to prepare an amendment to the indenture
and solicit approval for the proposed amendments and waiver. Whitebox Advisors
has agreed to deliver a letter of consent in favor of the proposed amendments
and waiver.

         The solicitation expires at 5:00 p.m., New York City time, on September
21, 2005, unless extended by Willbros. Willbros will announce any extensions of
the solicitation by press release no later than 9:00 a.m., New York City time,
the day after expiration of the solicitation.

         The solicitation presents certain risks for holders who consent, as set
forth more fully in the consent solicitation statement. This document contains
important information, and holders should read it carefully before making any
decision.

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         Willbros has retained Bear, Stearns & Co. Inc. to serve as solicitation
agent for the solicitation, and D.F. King & Co., Inc. to serve as the
information agent and tabulation agent.

         Questions regarding the solicitation may be directed to the
solicitation agent at (877) 696-2327 (toll free). Copies of the consent
solicitation statement and related documents may be obtained at no charge by
contacting the information agent by telephone at (888) 886-4425 (toll-free) or
(212) 269-5550, or in writing at 48 Wall Street, 22nd Floor, New York, NY 10005.

         This announcement is not a solicitation of consents with respect to the
notes. The solicitation is being made solely by the consent solicitation
statement. In any jurisdiction where the laws require solicitations to be made
by a licensed broker or dealer, the solicitation will be deemed to be made on
behalf of Willbros by the solicitation agent.

         Willbros Group, Inc. is an independent contractor serving the oil, gas
and power industries, providing engineering and construction, and facilities
development and operations services to industry and government entities
worldwide. For more information on Willbros, please visit our web site at
www.willbros.com.

This announcement contains forward-looking statements. All statements, other
than statements of historical facts, which address activities, events or
developments the Company expects or anticipates will or may occur in the future,
are forward-looking statements. A number of risks and uncertainties could cause
actual results to differ materially from these statements, including those
discussed above and such things as the potential for additional investigations,
fines and penalties by government agencies, the financial impact of the internal
investigation, litigation that may arise from the investigation, the outcome of
the potential SEC and Department of Justice investigations, including review and
restatement of its previously announced or filed financial results and the costs
and expenses associated therewith; the audit of the restated financial
statements; the identification of one or more other issues that require
restatement of one or more prior period financial statements; the completion and
audit of Willbros' 2004 financial statements; the communication by Willbros'
management and independent auditors of the existence of material weaknesses in
internal controls over financial reporting; availability of quality management,
availability and terms of capital; changes in, or the failure to comply with,
government regulations; ability to remain in compliance with, or obtain waivers
under, the Company's loan agreements and indentures; the promulgation,
application, and interpretation of environmental laws and regulations; future
E&P capital expenditures, oil, gas, gas liquids and power prices and demand, the
amount and location of planned pipelines, the effective tax rate of the
different countries where the work is being conducted, development trends of the
oil, gas and power industries, changes in the political and economic environment
of the countries in which the Company has operations, as well as other risk
factors described from time to time in the Company's documents and reports filed
with the SEC. The Company assumes no obligation to update publicly such
forward-looking statements, whether as a result of new information, future
events or otherwise.

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