Leaders of the International Monetary Fund, World Trade Organization and other agencies warned Monday that American protectionism could cause global economic damage, while the European Union backed a Group of Seven declaration that U.S. President Donald Trump abruptly refused to join.
President Donald Trump said Canadian Prime Minister Justin Trudeau "learned" from the mistake of criticizing him and it's going to cost Canada "a lot of money". "I know it didn't look friendly; it was reported as nasty both ways, I was angry with her - actually, we were just talking, the whole group, unrelated to everything, very friendly, waiting for the document to come back".
"And if it's not fixed, we're not going to deal with these countries".
U.S. trade advisor Peter Navarro, speaking on "Fox News Sunday", reinforced that message.
"There's a special place in hell for any foreign leader that engages in bad faith diplomacy with President Donald J. Trump and then tries to stab him in the back on the way out the door", Navarro said.
"Fair trade is now to be called fool trade if it is not reciprocal", said Trump, who flew from Canada to Singapore on Sunday to prepare for the first-ever summit between a USA and North Korean leader.
"We are like the piggy bank that everybody is robbing", he said.
Trudeau had used the word "insulting" several times in the last two weeks to describe Trump's tariffs, as the prime minister has taken issue with the fact they're being applied on the premise that Canada poses a national security threat to the U.S.
Reacting to Mr Trump's tweets, Mr Trudeau's office said: "We are focused on everything we accomplished here at the summit".
In response to initial tweets critical of her country and prime minister, Canada's foreign minister, Chrystia Freeland, said her nation "does not conduct its diplomacy through ad hominem attacks".
The US leader repeated once more that it would be a good idea for Russian Federation to return to the G7 and insisted that at the summit, some have liked the idea.
"That's what matters", he wrote.
Reneging on the commitments agreed in the communique showed "incoherence and inconsistency", it said in a statement.
Ms. May also rejected President Trump's suggestion that Russian Federation should be brought back into the G7.
Officials from European delegations quickly leaked copies of the joint statement, and it was published online moments before Trump tweeted.
In the end, Trump never visited the sessions on climate or the ocean, but held its own news conference, where he slammed "unfair trade" and promised to cut ties with countries that didn't adhere to a "zero tariffs", policy, then leaving for a summit in Singapore. The likelihood of a trade war between the United States and Canada appears to be on the rise, and both sides are mulling more trade barriers. Some of Trump's aides also lashed out at the Canadian prime minister. The compromise on that issue resulted in language that said "free, fair, and mutually beneficial trade and investment, while creating reciprocal benefits, are key engines for growth and job creation".
The British government has been eager to sign a trade deal with the USA after the United Kingdom leaves the European Union next year.