Meanwhile, US President Donald Trump left the summit early en route for Singapore to attend a historic meeting with North Korea's Kim Jong un, which will be held on June 12.
"I don't want us to keep inflating our language", she added, saying the word "depressed" was "already a lot, coming from me", in an ironic reference to her usual unflappable appearance.
Disagreement over the sunset clause was the deal breaker that scuttled a possible meeting between Trump and Prime Minister Justin Trudeau in Washington late last month in an attempt to bring the NAFTA talks to a conclusion. In another, Prime Minister Justin Trudeau can be seen standing behind the U.S. President, smiling, with Foreign Affairs Minister Chrystia Freeland at his side.
They built on the momentum Trump started a day earlier when he fired Twitter salvos from Air Force One, hours after departing the G7 summit, calling Trudeau "very dishonest and weak", among other things.
German Chancellor Angela Merkel said in a new interview Sunday that the European Union would implement counter-measures in response to President TrumpDonald John Trump McCain rips Trump over trade, tells allies: "Americans stand with you, even if our president doesn't" Head of Canada's auto parts industry association mocks Trump's threat of auto tariffs Dem leaders condemn Trump after reversal on G-7 communique endorsement MORE's decision to levy tariffs on the 28-member bloc.
"President Trump is targeting the dairy sector because he wants to dump USA dairy into Canada", Lampron told The Canadian Press, adding that Canada imports five times more dairy from the US than it exports.
Mr Trump, who was leaving the summit in La Malbaie early, told reporters the U.S. needed protectionist tariffs because "we are like the piggy bank that everyone is robbing". On the other hand, another social media user said, "It looks as if Madam Merkel is teaching The Donald a lesson!"
Mr Trudeau said: "Canadians, we're polite, we're reasonable but we also will not be pushed around". The United States pays enormous tariffs on dairy.
Mr Trump, who initially appeared ready to endorse the communique, pulled out after firing off a series of angry tweets aimed at Canadian premier Justin Trudeau. "He really kind of stabbed us in the back".
"I will blame them if they don't act smart and do what they have to do because they have no choice", he said.
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.