President Donald Trump signed an order Monday imposing global tariffs of 25% on all steel and aluminum imports, likely pleasing domestic steelmakers but hurting allies like Canada and Mexico.

The European Union plans to retaliate against the United States for new steel and aluminum tariffs. "Unjustified tariffs on the EU will not go unanswered—they will trigger firm and proportionate countermeasures,

The European Union said it would respond with "firm and proportionate countermeasures" after U.S. President Donald Trump's decision to impose tariffs on all steel and aluminium imports, escalating fears of a trade war.