One day after announcing new 10% tariffs on Chinese imports President Donald Trump says he could increase them even more. At the same time, Beijing is promising “necessary countermeasures” if any new duties go into effect.

Stock markets in France and Germany fell more than three percent. In the United Kingdom and Japan, they dropped more than two percent. Friday capped the Nasdaq’s worst week in 2019.

The back and forth has rattled global markets.  CGTN’s Toby Muse reports.

Markets around the world tumbled as soon as U.S. President Donald Trump tweeted a threat to levy a new 10% tariff on 300 billion dollars’ worth of Chinese goods.

Now, almost every Chinese import will be hit with extra U.S. taxes. These tariffs will take effect at the beginning of September. If they do, consumer goods like iPhones and toys will get more expensive during the holiday shopping season-when retailers make their biggest profits.

“China has to do a lot of things to turn it around. But, you’ll be seeing they’ve got to do a lot of things,” said President Trump. “It goes on Sept. 1 and frankly if they don’t do them, I can always increase it very substantially. In other words, I could increase it if I wanted to I could increase it to a very much higher number.”

The Associated Press cited economists estimating these tariffs could cost each U.S. household around $200 a year.

The world’s two largest economies have been slapping tariffs on each other in a protracted trade war. Even so, Washington’s biggest trade deficit remains with China, coming in for the first half of 2019 at 167 billion dollars, a drop of 10% from the same period last year.

The White House has also been renegotiating trade with the European Union and announced Friday that U.S. cattle-farmers will be selling more hormone-free beef to Europe. Trump said that the deal will give a boost to U.S. farmers – some of those hit hardest by the trade war with China.