The Scottish Government has called for Scotch to be defined in UK law in order to protect whisky exports after Brexit.
Scotland's Economy Secretary Keith Brown has written to UK ministers calling for protection of the Scotch whisky industry, in light of International Trade Secretary Liam Fox's visit to the US this week.
The industry is worth around £4 billion to Scotland in exports and an EU definition of whisky currently protects sales from sub-standard products.
Mr Brown said: "Aside from being a key part of Scottish culture and identity, our whisky industry supports around 20,000 jobs.
"The US made clear in the Transatlantic Trade and Investment Partnership discussions that they would support a relaxation of the definition of whisky, which would open the market up to a number of products which do not currently meet that standard.
"Whisky is a product which is worth around £4 billion to Scotland in exports.
"It is vital that we continue to have robust legal protection of Scotch whisky, which is why I have sought clarification from the UK Government as to whether Scotch whisky featured in discussions during last week's trade visit by the Secretary of State for International Trade.
"I am also demanding that the current EU regulations are guaranteed post-Brexit.
"After reports this week that the UK Government is contemplating trade deals that threaten the value and reputation of Scottish produce, once again we can see the confusion which is at the heart of the UK Government's Brexit position.
"We need to be sure that any future deals work for Scotland and are not threatening the livelihoods of our farmers and producers.
"This is why all four UK governments should have oversight of the negotiations to ensure, as far as possible, that the right outcomes for everyone are secured."
A UK Government spokeswoman said: "Scotch is a UK export success story and we will support the industry so that it continues to thrive and prosper post-Brexit.
"The UK Government has a strong relationship with the Scotch Whisky Association and is working closely with the industry as we aim to secure the best possible deal for the whole of the UK."
Rosemary Gallagher, Scotch Whisky Association head of communications, said: "To support jobs and growth in the Scotch Whisky industry after Brexit, we are looking for the government to prioritise a range of matters, including robust legal protection of Scotch Whisky in the EU and global markets.
"Regarding the EU whisky definition, all whisky produced or sold in the EU must be, among other things, matured for at least three years. We would be opposed to any weakening of the whisky definition as a result of trade negotiations with other countries or through any other means."