The World Trade Organisation (WTO) on Monday called for arbitration in a row pitting the United States against the European Union and others over a request for hundreds of millions of dollars in trade sanctions.
The EU and seven other members, including Japan, Canada and Brazil, want to retaliate against Washington for not lifting a trade law - the so-called "Byrd" amendment - already ruled illegal by the WTO.
They sought sanctions on US exports for the equivalent of the more than $700 million that Washington has raised and distributed to US firms under the controversial law over the three years since it came into force.
But, as expected, the United States opposed the level of sanctions, which meant that under WTO rules it was automatically put to arbitration.
The panel of judges, which will act as referee, officially has around a month from now to reach a decision, but such rulings have in the past often taken longer.
The law at the centre of the dispute obliges the government to distribute revenues from anti-dumping duties to US companies bringing the dumping complaint. The beneficiaries have been US ball-bearing, steel, candle, pasta and seafood companies, along with other businesses.
The spat is the latest in a series of disputes involving the government of US President George W. Bush, an avowed free trader who critics accuse of being reluctant to bow to WTO rules when they go against the United States.
"This is the first time in WTO history that so many members have acted (together)...in a single case," said Canada's trade envoy Sergio Marchi. "It is the clearest possible signal of the depth and breadth of concern," he added.
The administration, which missed a December 27 WTO-set deadline to lift the amendment, has promised to try again early this year, although it rejects the notion that the measure does direct harm to foreign companies.