A top European Union official, who is trying to head off a potential trade conflict, stressed the importance of active engagement and fairness in trade during a four-hour meeting with Trump administration officials on Wednesday.

Donald Trump’s tariffs are a headache for all his trade partners. But the U.S. president’s plan to impose ad hoc “reciprocal” levies on imports are a particular problem for the European Union. By enabling him to target whichever countries in the bloc he pleases,

European Commission President Ursula von der Leyen said during the Munich security conference Friday the European Union will respond if the United States imposes reciprocal tariffs.