Moscow was kicked out of the group, then the G-8, four years ago after it annexed Crimea.
On Sunday, Trump's chief economic adviser, Larry Kudlow, accused Trudeau of undermining the United States and its allies with comments at the G7 summit.
Maria Repnikova, director of the Center for Global Information Studies at Georgia State University in the U.S., said China makes Russian Federation look "stronger and more relevant" on the global stage. "We'll see how it all works out, but we've made a lot of progress, ' Trump said, sitting by Trudeau after talks that an official said were marked by 'strong disagreement" but 'not heated'.
To Trump's suggestion that Russian Federation be welcomed back to the group, allies had mixed responses.
In the message, Kim wished the strategic and traditional relations between North Korea and Russian Federation would become stronger and it hoped success for Putin in building a powerful Russian Federation. "All this makes me believe that the dialogue can be constructive", Putin said.
Trudeau addressed Trump by his first name off the top of their meeting and offered warm greetings.
"Putin is not our friend and he is not the President's buddy", Sasse said in a statement.
Tweeting in English, Macron stressed: "No leader is eternal".
Trump's remarks were the latest show of disunity between the USA and the other six nations meeting at a resort on the Saint Lawrence River this weekend.
The Trump administration announced two weeks ago that it would investigate whether auto imports hurt USA national security, the first step toward tariffs similar to the ones he imposed on steel and aluminum imports last week.
The meeting is getting under way a day after the president engaged in a Twitter spat with summit participants and announced he would leave the gathering before it is over.
The G-7 is made up of the USA and allies Britain, Canada, France, Germany, Italy and Japan.
Putin urges EU to pay attention to Russian speakers' rights in Baltics
"We have been a faithful player to this commitment, we've done our best, we've shown our good intentions".
Leading up to the meeting, French President Emmanuel Macron and Canadian Prime Minister Justin Trudeau openly criticized Trump's new tariffs.
It also calls for co-ordinated attribution of hostile activity so more countries name and shame perpetrators of cyber attacks and other abuses.
Such tumultuous trade policy has grown into a major irritant in relations with allies, including Canada and France, which had earlier been ready to go a long mile to build rapport with the maverick USA president (Forbes.ru, June 8). The president told reporters, "They have no choice. Not fair to our farmers!" He said the Chinese president was the only state leader to have celebrated his birthday with him, with the pair sharing a drink and sausage.
Kudlow says Trump won't let a Canadian prime minister push him around on the eve of his summit with North Korean leader Kim Jong Un.
He made the comment at the White House on Friday after hours of further escalating his rhetoric against longtime allies over US trade practices.
"As far as I know, the president of the United States said the U.S.is considering the possibility of regulating the additional supply of automotive equipment in the US market", he said.
"But I think this is a technicality", he said.
The U.S. president had also slammed America's Western trading partners, saying "all of these countries have been taking advantage of the United States on trade".
Little of that tension was on display when the cameras entered the rooms of the summit, however.
In his press conference, Trudeau had spoken of retaliatory measures that Canada would take next month in response to Trump's decision to slap tariffs on steel and aluminum imports from Canada, Mexico and the European Union.
Investors are also concerned about the future of the North American Free Trade Agreement, which Trump has threatened to terminate.
The president reiterated the idea that a trade agreement could take a different shape, namely, individual deals with Canada and Mexico. Trump said at the White House just before departing.More news: Chazelle's First Man, Official Trailer #1
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