U.S. President Donald Trump on Tuesday vowed to hit the European Union with tariffs and said his administration was discussing a 10% punitive duty on Chinese imports because fentanyl is being sent from China to the U.

In 2017, weeks after Donald Trump’s first presidential election victory, Xi Jinping became the first Chinese head of state to address the World Economic Forum in Davos, Switzerland — winning applause as he inveighed against protectionism and declared that a trade war would hurt both sides.

Donald Trump’s criticism of China on the campaign trail and after his election had raised the specter that Day 1 of his second presidency would reignite a trade war between the world’s two largest economies.