The US has stepped up pressure on the European Union over trade by taking the first steps towards imposing sanctions on European exports in retaliation for the EU's ban on hormone-treated beef. Among the products threatened if the sanctioned are finally imposed are likely to be some Irish food exports to the US.

The move, which follows last month's US decision to start implementing sanctions against the EU in their conflict over bananas, involved publication of a preliminary list of mainly agricultural exports that could be subject to 100 per cent tariffs.

Exports on the list include beef, poultry, ham, cheese, truffles and motorcycles. The US says the annual value of European exports on the list exceeds $900 million. Ireland exports ham and cheese products to the US, although the extent to which these products will be affected will depend on the precise terms of the US list.

A spokesman for Bord Bia last night said that they were closely monitoring the situation and would be in touch with any companies likely to be affected.

In contrast to the EU's angry reaction to US measures over bananas, yesterday's announcement drew a low-key response from Brussels.

The EU has until May 13 to comply with a World Trade Organisation ruling that the ban violates trade rules, because it is supported by no scientific evidence that hormone-treated beef is unsafe. The US says if no settlement can be reached by May 13, it will ask the WTO for authorisation to implement the sanctions, which would probably take effect in June.