New York, November 09, 2012 -- Willbros has amended its credit agreement to extend the maturity date of its senior secured credit facility and to modify the debt covenants and increase the amount of funds available for borrowing under certain conditions. The company also received incremental term loans of $60 million. These amendments have addressed some of the debt maturity and liquidity concerns that led to our negative outlook in May of this year. However, recent operating results have been weak and the company is expected to generate negative free cash flow this year. In addition, this is the second time the company has been forced to amend its credit facility within the past 20 months and it has not addressed its longer term financing needs. Therefore, Moody's is maintaining the company's B3 corporate family rating and our negative outlook.

Willbros United States Holdings, Inc. is a wholly-owned subsidiary of publicly traded Willbros Group, Inc (WGI) and is headquartered in Houston, Texas. The company provides engineering and construction (E&C) services to the oil, gas and power industries primarily in North America. WGI reports its results in three segments: Oil & Gas (59% of revenues; 30% of backlog) is focused on the U.S. market and specializes in pipelines and associated facilities and provides maintenance and turnaround services for refineries; Canada (8%; 15%) provides E&C services to the oil sands industry; and Utility T&D (33%; 55%) provides end-to-end infrastructure construction services, primarily for the electric and natural gas utility end-markets. The Utility T&D segment derives roughly 70% of its work under Master Service Agreement ("MSA") contracts with the remainder stemming from projects that are mostly fixed price and competitively bid. Willbros' revenue for the 12 months ending September 30, 2012 was $1.9 billion and its backlog totaled $2.3 billion, of which $1.1 billion is expected to be realized in the next twelve months. Approximately 77% of Willbros' backlog is in the US, 16% in Canada and the remainder mostly in the Middle East and North Africa.

Michael Corelli Vice President - Senior Analyst Corporate Finance Group Moody'sInvestors Service, Inc.250 Greenwich StreetNew York, NY 10007 U.S.A. JOURNALISTS: 212-553-0376 SUBSCRIBERS: 212-553-1653Brian Oak MD - Corporate Finance Corporate Finance Group JOURNALISTS: 212-553-0376 SUBSCRIBERS: 212-553-1653 Releasing Office: Moody's Investors Service, Inc.250 Greenwich StreetNew York, NY 10007 U.S.A. JOURNALISTS: 212-553-0376 SUBSCRIBERS: 212-553-1653(C) 2012 Moody's Investors Service, Inc. and/or its licensors and affiliates (collectively, "MOODY'S"). All rights reserved.

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