The United States has slapped tariffs of up to 25% on high-value Irish exports.
The Trump administration claims EU governments have illegally subsidised aircraft manufacturer Airbus.
Farmers and dairy industry bosses will be impacted by the news this morning.
Last night, officials in the United States dropped a list of goods being hit with tariffs of up to 25%.
Butter, cheese and yoghurt - along with pork products - all make the list.
It is a threat to firms like Ornua, which has developed a large market for brands like Kerrygold in the States.
Baileys and other Irish liqeurs also face a tariff hit.
But Irish whiskey exports from south of the border seem to have enjoyed a narrow escape.
US officials have slapped a 25% tariff on single-malt whiskies coming from the UK but not on whiskies exported from the Republic.
Aoife Clarke from Drinks Ireland Spirits says they are still disappointed.
"Our organisation represents the island of Ireland. Irish whiskey is an island of Ireland product," said Ms Clarke.
"So if you hit the north of Ireland, you hit the Republic of Ireland as well.
"It's not separated in that way so it's a very disappointing day."