A UNION is seeking urgent talks with the American Embassy over plans by President George W Bush to impose new duties on US steel imports.

Mr Bush is proposing measures which could lead to new tariffs on the import of steel products, hitting steelmakers across the world, including Corus.

The company said suggestions that 18,000 jobs could be lost and factories closed were "completely over the top", but an official acknowledged more jobs could be under threat.

A spokesman said the company, which is already cutting its UK workforce by 6,000, including more than 1,100 on Teesside, was opposed to the tariffs.

However, it will support other proposals by Mr Bush to cut subsidies to steel firms and reduce excess capacity of steel production.

Union leaders have voiced concern about the threat of job cuts, and will seek talks with British Government officials as well as the US Embassy.

Sir Ken Jackson, general secretary of the Amalgamated Engineering and Electrical Union, said: "This would be extremely damaging to the UK steel industry and would come as another blow to the Corus workforce."

Sir Ken confirmed he would be contacting the US Embassy to seek clarification of any new tariffs.

The news was met with caution on Teesside, with Tony Poynter, chairman of the multi-union steel committee, stressing that it was too early to say what impact such proposals would have on the area.

He said: "Teesside does not export a lot of steel to America so we just have to keep an eye on what is going on."

He said it was too early to tell if was going to be another blow for Teesside - his understanding was that Mr Bush had only put forward proposals, and nothing concrete had been decided.

Michael Leahy, general secretary of the Iron and Steel Trades Confederation, said that he will be contacting the Department of Trade and Industry this week about the new threat to jobs.