Donald Trump announced sweeping tariffs on some of its largest trading partners on Wednesday, upending decades of US trade policy and threatening to unleash a global trade war on what he has dubbed “liberation day”.

“This is one of the most important days, in my opinion, in American history,” Trump said, speaking on the White House lawn. For decades America had been “looted, pillaged and raped” by its trading partners, he said. “In many cases, the friend is worse than the foe.”

Trump said he intends to impose “reciprocal tariffs” on foreign imports, charging US trading partners the same duties imposed by the country of origin on the same goods. Among other examples, Trump criticized European bans on imported chicken, Canada’s tariffs on dairy, and Japan’s levies on rice.

Trump said the US would charge half of the fees he feels trading partners unfairly impose on the US because the US people are “very kind”.