​"He's a pathetic little man-child."

Roland Paris, former ​foreign policy adviser to Canadian Prime Minister Justin Trudeau, called Trump a "pathetic little man-child" on Twitter Saturday in ​response to President Donald Trump tweeting that Trudeau was "dishonest and weak."

The exchange via Twitter comes after a highly-anticipated ​G7 Summit, which predictably displayed high ​tensions over ​​tariffs involving the United States and fellow members of the G7.

Trump cut his stay at the summit short. On Saturday afternoon, after Trudeau took a public jab at the US's new tariffs on Canadian imports, Trump took umbrage on Twitter.

The president then continued to attack Canada, and the summit as a whole, announcing on Twitter that the US will not co-sign the group's joint statement.

Twenty minutes later, Paris responded to Trump.

Trump implied that the reason Trudeau's statement caused such an uproar was that it came after the US delegation had left the summit -- in other words, behind Trump's back. However, Cameron Ahmad, who serves in communications for the Prime Minister, said that Trudeau has always been upfront with Trump.

Chrystia Freeland, Canada's foreign affairs minister, responded to Trump's statements in ​press conference on Sunday, saying that "Canada does not believe that ad hominem attacks are a particularly appropriate or useful way to conduct our relations with other countries.”


Democrats, Republicans, and foreign leaders alike have criticized Trump for what they feel is poor diplomacy and leadership. 

John McCain Tweeted on Saturday that "Americans stand with you, even if our president doesn't."

Nancy Pelosi feels that Trump is "alienating us from our allies."

Chuck Schumer compared the US to Russia, saying the nations' diplomatic and national security strategies are becoming indistinguishable.

“In a matter of seconds, you can destroy trust with 280 Twitter characters,” German Foreign Minister Heiko Maas said to ​Reuters.