The EU has warned Donald Trump it is ready to retaliate against “hurtful” tariffs as the US president kick-started a global trade war. European leaders including Olaf Scholz, the German chancellor, warned that the EU had “its own courses of action” after the new president said the bloc had treated the US “terribly” and would be next in line for tariffs after Canada, China and Mexico. It comes as Sir Keir Starmer is set to be the UK’s first Prime Minister to attend an EU summit since Brexit, when he travels to Brussels on Monday as part of a “reset”...