Trump was the last G-7 leader to arrive and will probably be the first to leave on Saturday when he sets off for his nuclear summit with North Korea's Kim Jong Un in Singapore.
Ahead of the encounter, the allies made no secret of their anger at Trump s stance, pointed starkly to fears that he is undermining the rules-based world order and driving former U.S. friends into a damaging trade war.
The leaders from Britain, Germany, France, Canada, Japan and Italy may conclude the summit today with a forceful joint statement issued without Trump's signature, a striking departure from the usual display of cooperation that has punctuated meetings between the United States and its most important allies.
Trump sounded optimistic on that front, saying during his meeting with Trudeau that a joint statement was still possible. Shortly after that statement was published online, Trump complained about comments made by Trudeau and revoked his support.
Trump, who is in Singapore for negotiations with North Korea, continued to rip into USA trading partners late Sunday night Eastern Time, repeating complaints about the United States trade deficit and contributions to NATO. "And that's why we need to increase our defence spending", Merkel said.
Earlier, Mr Trudeau had spoken of retaliatory measures that Canada would take next month in response to Mr Trump's decision to slap tariffs on steel and aluminum imports from Canada, Mexico and the European Union.
When the two leaders finally met late in the day, Macron was first to reach out to shake Trump's hand and the last to let go, gripping it so tight his fingers left white marks - a reprise of the long, exaggerated handshake that marked the first meeting between the two leaders past year.
Trump criticizing the Group of Seven nations host and stepped back from the generally positive tone that had ended the two-day meeting in Quebec.
With a US-German trade war more likely by the week, Berlin is reluctantly drawing up a new strategy to deal with Washington, a radical break with 70 years of foreign policy. "After a long day of work and very direct dialogue, we are actively seeking an ambitious agreement", an English translation of Macron's tweet reads.
Japanese Prime Minister Shinzo Abe did not show a clear stance on the issue, the official said. Investors are also concerned about the future of the North American Free Trade Agreement, which Trump has threatened to terminate. Trump will skip sessions on climate change and the environment.
Trump also expressed his belief that Russian Federation should be reinstated into the group of leading industrialized nations, telling reporters "Russia should be in the meeting, should be a part of it".