Larry Kudlow, who is the director of the National Economic Council, made the comments on CNN's State of the Union, in justifying Trump's decision to back out of a joint statement made by the countries that attended this weekend's G-7 summit in Canada.
Later on June 9, after he left the G7 summit, Trump unleashed a barrage of tweets, likely while he was aboard Air Force One on his way to Singapore for his summit with North Korean leader Kim Jong Un - "Just left the @G7 Summit in handsome Canada".
As President Trump was leaving the G7 summit onboard Air Force One, Trudeau held a press conference in which he said that Canada would not be "pushed around" by the USA on trade.
Kudlow, who was in Canada with President Trump for the G-7 meeting, told CNN on Sunday that the US had come to an agreement with the other highly-industrialized nations in the group on a joint communique until Trudeau's "sophomoric play".
U.S. President Donald Trump shakes hands with Canada's Prime Minister Justin Trudeau in a bilateral meeting. On Saturday, he called the Canadian prime minister "very dishonest and weak".
"Canada does not conduct its diplomacy through ad hominem attacks. and we refrain particularly from ad hominem attacks when it comes to a close ally", Canadian foreign minister Chrystia Freeland told reporters on Sunday.
Mr Trudeau had sought to play down personal clashes with Mr Trump as he wrapped up the summit, calling the meeting "very successful" and saying he was "inspired by the discussion". "As Canadians, we are polite, we're reasonable, but also we will not be pushed around".
Winner of $315 million Powerball jackpot comes forward
Originally from Africa, Souami came to the United States in 1996. "When he told me we won, I had to see for myself", said Joe. Tuesday's Mega Millions jackpot will be worth $144 million ($85 million cash).
Trump, who seemingly chose to pour out his grievances with the rest of the Western world at once, then lashed out at "these same countries that rip us off on Trade" for their unwillingness to stump up their fair share for North Atlantic Treaty Organisation.
In response to Mr Trump's decision to withhold U.S. support for the summit conclusions, a senior United Kingdom government source said: "We stand by the commitments made in the G7 communique".
But, Trump's defenders today say that he is simply standing up for America. "Well, the in-factual, the non-factual part of this was they have enormous tariffs", Kudlow said.
Canadian Prime Minister Justin Trudeau has vowed retaliatory action next month over United States tariffs on steel and aluminium. "That's what weak, dishonest Justin Trudeau did".
In a news conference after the summit, Mr Trudeau had said that while he did not want to "punish American workers", his job was to protect Canadians and as such he would press ahead with tariffs on some USA imports.
"Business confidence, and subsequently capital spending, is at risk if this tension continues through the summer", said Tai Hui, J.P. Morgan Asset Management Chief Market Strategist for Asia Pacific.
The now-rejected communique acknowledged the importance of "free, fair and mutually beneficial trade and investment".
Internationally, one European diplomat says the rest of the G7 will carry on despite the president's online attack against Trudeau and his decision to pull out of the final G7 communique. "Our Tariffs are in response to his 270% on dairy!" Kudlow said on CNN.