By a vote of 5-0, with one commissioner not participating, the US International Trade Commission (ITC) made a preliminary determination that imports from the six countries had injured or threatened to injure domestic producers.

The United Steelworkers of America and five US stainless steel bar firms filed the case in late December, asking for anti-dumping duties of up to 268 per cent.

The group charged the six countries with selling stainless steel bar in the US market below fair market value and accused the Italian government of subsidising production. William Pendleton, director of corporate affairs for Carpenter Technology Corp, said the Wyomissing, stainless steel bar producer was "very pleased" with the ITC vote.

"We believe this is the proper determination by the commission and we are ready to go on to (the Commerce Department) with the dumping determination," Mr Pendleton said.

The commerce department is expected to announce by June its preliminary determination of dumping by each country. That would return the case to ITC to make a final injury determination before any anti-dumping duties are imposed.

In late December, the ITC also approved anti-dumping probes against hot-rolled steel imports from 11 countries, including Argentina, China, India, Indonesia, Kazakhstan, Netherlands, Romania, South Africa, Taiwan, Thailand and Ukraine. US steel producers complain they are besieged by unfairly traded imports from around the world.