Irish exporters have yet to feel the effects of punitive tariffs which the US is imposing on certain EU goods in retaliation for Europe's ban on US hormone-treated beef. The 100 per cent tariffs which mainly affect Irish pork products represent the opening of a second front - on top of the ongoing dispute over bananas - in the trade wars with the US.

Initially, domestic exporters were expected to be hit for £10 million (€12.7 million) when the US Department of Commerce published its tariff list earlier this year, but a revised list which came into effect on Thursday is estimated to affect only £800,000 worth of exports, according to Mr Owen Brooks, director of international markets at Bord Bia. The trade war goes back to the EU ban on artificially (hormone) treated US beef in 1989. Protracted discussions have taken place since, resulting in an arbitration court of the World Trade Organisation lifting the ban.

The EU ignored the WTO ruling, it is believed, based on its belief that EU consumers have made clear they do not want hormone treated beef, according to sources in the Department of Agriculture.

The revised tariff list will hurt French, German and Italian exporters most, with the former two countries absorbing at least 50 per cent of the $117 million (€109 million) worth of tariffs, according to Mr Brooks. The UK, which is unopposed to US hormone treated beef, is almost unaffected by the tariffs imposed by the Department of Commerce.

The Irish food and drink export market to the US was worth £162 million in 1998, and the current tariffs which mainly affect Irish pork products, represent 0.4 per cent of the total food and drink export business. But the Irish Exporters' Association believes the cumulative effect on exports could be much more "significant".

"An image is being built up in the minds of US importers and distributors that products from Ireland could be problematic and they may have to pay [100 per cent duty] along the line, even on products that are not affected; they may start backing off Irish exporters," says IEA chief executive, Mr John F Whelan.

Exporters fear they may find it more difficult to sell to Europe, their main market, because it would be awash with goods normally going to the US.

"It's certainly a very bad day for Irish exporters that we now have a second trade dispute kicking into place with punitive effects which ultimately can effect our whole ability to trade with the US," says Mr Whelan.