President Donald Trump said on Friday that he was "recommending a 50% tariff on the European Union" after complaining about stalled trade negotiations.
Trump wrote on Truth Social that the steep new tariffs on imports would begin on June 1.
He added that the European Union "has been very difficult to deal with. Our discussions with them are going nowhere!"
Trump's announcement came less than 30 minutes after he threatened to impose tariffs of at least 25% on Apple if the company did not begin manufacturing iPhones in the United States.
The announcement led to an immediate decline in European stock indices. Germany's DAX index fell 1.85% within ten minutes of the announcement, reaching 23,475 points, and continued to decline, losing more than 2% later.
Trump justified the move by citing an annual trade deficit of more than $250 billion with the European Union, and said that current trade talks were "going nowhere."
He also threatened to impose an additional 25% tariff on Apple products manufactured outside the United States, causing the company's shares to fall by 4%.
There was no immediate official response from the European Union, but Brussels is expected to hold emergency meetings to discuss an appropriate response. The EU previously responded to Trump's tariffs by imposing retaliatory tariffs on €26 billion worth of US products.
This move comes at a sensitive time in US-EU relations and could lead to an escalation in the trade war between the two sides. Global markets are expected to closely monitor the developments in this dispute and its impact on the global economy.