The United States won a landmark victory at the World Trade Organization in Boeing's fight against European government subsidies for rival aircraft manufacturer Airbus, U.S. trade officials said.

"These subsidies have greatly harmed the United States, including causing Boeing to lose sales and market share," U.S. Trade Representative Ron Kirk said in a statement. "The ruling helps level the competitive playing field with Airbus."

A WTO dispute settlement panel in Geneva was to release its long-awaited final ruling in a case the United States brought several years ago.

A second panel is expected to release a confidential preliminary decision in a EU countercomplaint against U.S. support for Boeing on July 16.

At the heart of the U.S. case was a complaint that European government "launch aid" loans were illegal subsidies.

"What emerges clear as day from this panel report is that Europe has never been able to provide launch aid in a manner that is consistent with its WTO obligations," USTR General Counsel Tim Reif said.

"This panel report should therefore be a strong signal to the European Union and the member states to refrain from future launch aid disbursements," Reif said. (Reuters)