Other Western powers dismissed U.S. President Donald Trump's suggestion of inviting Russia back into the Group of Seven, with German Chancellor Angela Merkel saying that won't happen until "progress" is made resolving the conflict in eastern Ukraine.
European Union countries, which make up four of the group's seven members, ahead of the summit "agreed that a return of Russia to the G7-format summits can't happen until substantial progress has been made in connection with the problems with Ukraine," Merkel said as the summit began in Quebec, Canada late on June 8.
Russia was expelled from the group four years ago after annexing Ukraine’s Crimea Peninsula and fueling a war in eastern Ukraine that has killed more than 10,300 people.
While Merkel said "the common view" in Europe is to continue to exclude Russia, Italy's new Prime Minister Giuseppe Conte later echoed Trump's call for returning Russia to the "negotiating table" in a post on Twitter.
Trump had said on his way to the summit: "You know, whether you like it or not, and it may not be politically correct, but we have a world to run and the G7, which used to be the G8, they threw Russia out. They can let Russia come back in, because we should have Russia at the negotiating table."
Canada, whose Prime Minister Justin Trudeau is hosting the summit, had an indignant reaction to Trump's suggestion.
"Russia made clear it has no interest in behaving by the rules of Western democracies," said Canadian Foreign Minister Chrystia Freeland. "There are no grounds whatsoever to bring Russia, with its current behaviour, back to the G7."
U.S. allies at the summit said they were stunned by Trump's friendly gesture toward Russia, especially in light of his move last month to cite "national security" reasons for threatening to impose tariffs on the steel imports of major U.S. allies, in a move that markets fear could spark a trade war.
"We are very clear that Canada does not pose a national security threat to the United States," Freeland said, calling Trump's move on tariffs "an illegal act" that "is absolutely unjustified."
The wrangling over whether Russian President Vladimir Putin should be welcomed back to the elite group of major Western nations came as the summit opened with sharpest divisions in recent history between the United States and its top allies on issues ranging from global trade and tariffs to the international agreements on climate change and Iran's nuclear program.
EU President Donald Tusk said he fears the deep divisions that have opened up between the United States and its closes allies may end up unravelling the post-World War II and post-Cold War world order they worked for decades to build together.
"It is evident that the American president and the rest of the group continue to disagree on trade, climate change, and the Iran nuclear deal," Tusk said when he arrived in Canada.
"What worries me most, however, is the fact that the rules-based international order is being challenged, quite surprisingly not by the usual suspects but by its main architect and guarantor, the United States," he said.
Tusk said he and other European leaders came to the summit prepared to keep trying to persuade Trump, who campaigned for office questioning such global institutions as NATO and the World Trade Organization, to rejoin the G7 group's previous consensus on the rules of trade, security, and other matters.
"Naturally we cannot force the U.S. to change their mind," he said. "At the same time we will not stop trying to convince our American friends and President Trump that undermining this order makes no sense at all, because it would only play into the hands of those who seek a new post-West order where liberal democracy and fundamental freedoms would cease to exist."
Many U.S. legislators, both Republicans and Democrats, have also been concerned about Trump's departure from past U.S. views on trade, Russia, and the international order.
"We need the president to be able to distinguish between our allies and adversaries, and to treat each accordingly," said Senate Democratic Leader Chuck Schumer.
Republican Senator Ben Sasse said that Trump should understand that "Putin is not our friend, and he is not the president's buddy. He is a thug using Soviet-style aggression to wage a shadow war against America, and our leaders should act like it."