Single malt whisky exported from Scotland to the United States is set to be hit by a 25 per cent tariff in a fortnight's time.
The new duty will come into effect on 18 October.
The levy is part of a raft of measures being imposed by the US under president Donald Trump in retaliation against EU subsidies given to aircraft maker Airbus.
Scotch whisky exports to the US last year were worth $1.3 billion (£1bn).
Karen Betts, chief executive of the Scotch Whisky Association, branded the tariffs as substantial.
"This is a serious situation for the industry," she said.
"We heard overnight that a 25 per cent import tariff will be imposed on all single malts into the United States and also all Scotch whisky liqueurs, and that's from a position of zero.
"We've had a zero tariff on imports to the United States for the past 25 years, so this is quite a hike."
Other goods being targeted include popular export items and gifts from Scotland such as cashmere sweaters, dairy products and pork.
The tariffs will also apply to olives, biscuits, books and some machinery.
Brussels has threatened to retaliate similarly against US goods.
Scottish Labour's shadow Cabinet secretary for finance Rhoda Grant said: “This will be a serious blow to the Scotch whisky industry.
“People’s jobs and living standards should not be put at risk because of a dispute between politicians.
“It is no surprise Donald Trump doesn’t care about this. He has spent his whole life using his inherited wealth and power to exploit working people.
“The UK Government must do all it can to ensure the United States reverses this decision.”
Scottish Conservative shadow finance secretary Murdo Fraser said: “This is obviously a very serious blow to the Scotch whisky industry.
“We will be speaking to our colleagues in the UK Government to see what can be done to sort this out.
“Ultimately, the responsibility here lies with the EU as it stands, and they are the ones who will need to explain to the sector why this has happened.
“This is something that needs to be resolved as a matter of urgency.”