"That's what bad-faith Justin Trudeau did with that stunt press conference".
The Trump administration confirmed on May 31 it would apply additional tariffs on steel and aluminium imports from Canada, Mexico and European Union countries, ending a two-month exemption period.
The tweets Mr Trump posted after the G7 contained direct attacks on the Canadian PM.
"We're like the piggy bank that everybody's robbing, and it ends", Mr. Trump told reporters at a press conference at the end of the meeting, just before he jets off to Singapore to meet with North Korea's leader.
He also called Trump's meeting with North Korean ruler Kim Jong Un Tuesday "far more important" than the G-7. Feds bust massive wire fraud scheme MORE (R-Ariz.) on Tuesday questioned why the Republican party is not standing up more forcefully against President TrumpDonald John TrumpSanford at risk in primary shadowed by Trump McConnell cements his standing in GOP history Ready for somebody?
The president has made a lot of noise at this year's G7 event in the Quebec town of La Malbaie - first by launching a Twitter attack on Canada's trade policies before the summit and then for suggesting Russian Federation be invited to re-join the alliance. "It seems to me that despite our frictions with Canada - and we have had trade disputes in the past and we have issues with the Canadian subsidies right now - that we need to recognize that Canada has been a close friend, a reliable ally and is one of our biggest trading partners". I think he should apologize to the prime minister.
As he flew from Canada to Singapore on Saturday night, Mr Trump displayed his ire via Twitter, which he also employed to insult Mr Trudeau as "dishonest" and "weak". He says that we are the problem with tariffs. "It's very unfair, and it's very unfair to our workers, and I'm gonna straighten it out".
Hours after Mr Trump withdrew his support for the joint statement and attacked Mr Trudeau, Mr Kudlow and trade adviser Peter Navarro drove the message home on Sunday morning news shows in an extraordinary assault on a close United States ally and neighbour.
Tensions threatened to boil over when French President Emmanuel Macron, on the day before the start of summit, said the other 6 countries might sign a joint statement without the U.S.
The Americans' criticism of Trudeau left a former Canadian prime minister, Stephen Harper, stumped. "The Prime Minister said nothing he hasn't said before - both in public, and in private conversations with the President", the office added.