U.S. President Donald Trump has said he will impose tariffs on imports of steel and aluminium and raise rates to match those of other countries in the coming week. The United States and European Union have the world's largest commercial relationship,

The European Union plans to safeguard its economic interests by imposing countermeasures in response to the U.S. tariffs, according to EU officials.

President Trump’s threats are carrying more weight after his moves against Canada, Mexico and China. Europe has been preparing for the possibility of a trade war for months.