May 12 (Bloomberg) -- A World Bank court today ruled against Argentina in the first decision stemming from more than 30 claims that allege the government broke contracts around the time of its 2001 debt default, a senior Argentine official familiar with the case said.

The World Bank said in a statement a three-member panel issued a ruling in the case of CMS Energy Corp. against Argentina, and declined to give details. CMS, owner of Michigan's largest natural gas utility, alleged the government broke a contract by preventing the company from raising prices.

A decision in favor of CMS would put pressure on the government to settle with other companies suing in the World Court, said Rafael Ber, an analyst at Buenos Aires-based Argentine Research. CMS has been unable to raise prices since the government froze utility rates after the default.

``This tips the balance toward utilities in their confrontation with the government,'' Ber said. ``The more rational response from the government would be to speed up negotiations on rates so that more demands against Argentina are dropped.''

Jeff Holyfield, a spokesman for Jackson, Michigan-based CMS, said the company was still reviewing the ruling. Argentine Justice Minister Horacio Rosatti was meeting with President Nestor Kirchner and unavailable for comment, Rosatti's office said.

Companies, including the world's second-biggest water company Suez SA, and Germany's largest engineering company Siemens AG, are suing Argentina in the World Bank tribunal on allegations the government broke contracts.

AES Corp., which distributes electricity in the province of Buenos Aires, last month agreed to withdraw its complaint from the World Bank tribunal after the government allowed it to raise prices.

The case was filed by CMS Gas Transmission Co. The World Bank tribunal, called the International Center for Settlement of Investment Disputes, was created in 1966 to speed the process for settling disputes between foreign investors and governments.

To contact the reporter on this story: Andrew J. Barden in Buenos Aires barden@bloomberg.net

Last Updated: May 12, 2005 20:00 EDT