Trump tweeted his reversal after what he called "false statements" by Canadian Prime Minister Justin Trudeau, who he labeled "dishonest and weak".
The Canadian prime minister's office responded to Trump's tweets accusing Trudeau of "false statements" on Saturday, saying that the Prime Minister said nothing during the G7 summit that he had not said previously.
The G7 summit came after the Trump administration announced last week to impose tariffs on steel and aluminum imports from the European Union (EU), Canada and Mexico, which has drawn strong opposition from the domestic business community and quick retaliation from USA major trading partners.
The spat drew in Germany and France, who sharply criticized Trump's decision to abruptly withdraw his support for a Group of Seven communique hammered out at a Canadian summit on Saturday, accusing him of destroying trust and acting inconsistently.
"International cooperation can not depend on being angry and on sound bites". "We have a world to run and in the G7, which used to be the G8 they threw Russian Federation out, they should let Russian Federation come back in", he said upon arriving at the G7 meeting in Canada's La Malbaie.
Sen. Ben Sasse of Nebraska, a Nebraska Republican, said in a statement: "If the president is actually serious about leading the expansion of a G-7 no-tariff, free-trade agreement, that's tremendous, tremendous news - for the USA and for the free nations of the world".
Moreover, after departing from the Quebec summit for Singapore, Donald Trump has slammed Canadian Prime Minister's remarks at the G7 news conference, where he said Canada would not be pushed around, as "very dishonest and weak".
He also announced over Twitter he'd instructed US officials to not endorse the statement, which serves as a declaration and recap of what was decided in the meeting.
"Canadians. stood shoulder to shoulder with American soldiers in far off lands in conflicts from the First World War onward", the prime minister said at a press conference at the end of the summit.
"So we are either going to have NAFTA in a better negotiated form or we're going to have two deals".
Trump infuriated his G7 allies recently by slapping them with the hefty tariffs on steel and aluminum - a move that prompted Canada and the European Union to threaten duties of their own.
Here's a World Bank graph of trade-weighted average tariffs for the G7 countries - with United States almost identical to UK/Italy/France/Ger, higher than Japan/Can.
That leaves Trump diametrically opposed with Canada, which says renegotiating the deal every five years would create perpetual uncertainty and harm long-term investment.
The president also tweeted that he was revoking USA endorsement of the summit's final joint statement. "We are open to dialogue, but that does not mean transforming a defined process, linked to the implementation of the Minsk accords", he said.
The G7 joint communique, which advocates a "rules-based trading system", was reached despite tension over USA tariffs on steel and aluminium imports, reported BBC.
Sharply criticizing Trump's remarks on tariffs, Trudeau promised that Canada would answer with its own on July 1 unless the US reversed course.