President Donald Trump has announced that the European Union and Mexico will face a 30% tariff on imports to the US from 1 August.
He warned he would impose even higher import taxes if either of the US trading partners decided to retaliate.
The announcement was made in two letters posted on Trump's Truth Social website. Similar letters were sent this week to several other countries.
The 27-member EU - America's biggest trading partner - said earlier this week it hoped to agree a deal with Washington before 1 August.
In the letter to European Commission Ursula von der Leyen, Trump wrote: "We have had years to discuss our trading relationship with the European Union, and have concluded that we must move away from these long-term-large, and persistent, trade deficits, engendered by your tariff, and non-tariff, policies and trade barriers."
"Our relationship has been, unfortunately, far from reciprocal," the letter added.
The EU has been a frequent target of Trump's criticism, and in April Washington announced levies of 20% on European goods.
In 2024, the US trade deficit with the bloc was $235.6bn (€202bn; £174bn), according to the office of the US trade representative.
English (US) ·