Two out of five US firms with a base in this country are considering moving elsewhere in Europe because of Brexit, a report shows.
Research by international law firm Gowling WLG also revealed that more than half of US companies which export to the EU are more likely to bypass the UK following the referendum result.
The study of more than 500 company executives of US firms, most having a UK base, showed differences in sectors, with those in food and beverage, life sciences and financial services most likely to consider relocating, and aerospace least likely.
Uncertainties surrounding Brexit, in particular the delay caused by issues such as Article 50, are threatening trading links between the UK and the US, said the report.
Bernardine Adkins, of Gowling WLG, said: “The strong UK-US trade relationship that has been carefully nurtured over the past 50 years is in serious jeopardy.
“This is despite a wide consensus amongst US firms that the unique dynamics of the UK market and its access to the rest of the EU drive their preference for doing business here.
“Concerns that Brexit will have an effect on current investment decisions mean this needs addressing now, not later.”