Merchants worried that a trade war could wreak financial havoc in a region that has a robust business exporting the world’s finest bubbly to the United States.

In a post to Truth Social, the social media company the president owns, Mr. Trump said the U.S. will retaliate against the European Union after it announced Wednesday that it would be increasing tariffs on U.

U.S. President Donald Trump on Thursday threatened to slap a 200% tariff on wine, cognac and other alcohol imports from Europe, opening a new front in a global trade war that has roiled financial markets and raised recession fears.