In an extraordinary closing press conference, the US president attacked the world’s other economic powers, telling reporters: “We are like the piggy bank that everyone is robbing.”
Mr Trump said he would be able to judge “within a minute” of meeting North Korea’s leader on Tuesday whether he was serious about giving up his nuclear weapons.
And he insisted his relationship with other G7 leaders was “a 10”, despite deep rifts over Russia and steel tariffs – but, strikingly, without mentioning the British prime minister.
“I would say that the level of relationships is a 10. We have a great relationship – Angela [Merkel] and Emmanuel [Macron] and Justin [Trudeau],” he said.
The snub to Ms May came despite her praising Mr Trump’s positive contribution to the G7 when she spoke to journalists on the flight out to the summit in Canada.
However, there have been claims the US president has told allies that he resents her “school mistress” tone – and he snubbed the idea of formal talks between the pair at the two-day get-together.
Ms May also joined other Western leaders in rejecting Mr Trump’s call for Russia to be readmitted to the G7, because of the “malign” poisoning of ex-spy Sergei Skripal.
On tariffs, the president warned the EU would be “making a mistake” if it carried through its threat to retaliate, saying. “We can’t lose. They do so much more business with us than we do with them.”
He accused EU countries of behaving in a “brutal” fashion towards the US by denying open access to its markets. “The gig is up. They can’t believe they got away with it,” he added.
Mr Trump also continued to insist the gathering should be expanded back to the G8, saying: “I think it would be an asset to have Russia back in.
“I think the G8 would be better, I think having Russia back in would be a positive thing. We are looking for peace in the world, we are not looking to play games.”
By walking out early, Mr Trump left before the summit got around to discussing climate change and damage to the oceans.
At the start of the day, the US president arrived late for a breakfast meeting of G7 leaders and members of the Gender Equality Advisory Council.
Mr Trudeau, the Canadian prime minister, spoke for several minutes with all the other G7 leaders were present – but one empty chair.
Isabelle Hudon, Canada’s ambassador to France, was speaking when Mr Trump finally arrived in the room. Security officers had to open a path for him through a mob of journalists.
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