"In conveying that message I used language that was inappropriate and basically lost the power of that message", Navarro said at the Wall Street Journal's CFO Network conference in Washington. "That was my mistake, those were my words".
Speaking for the first time about the acrimonious conclusion of the Group of Seven meeting in Quebec over the weekend, Trump said he felt Trudeau had mischaracterized the US position in a press conference after the summit.
Before flying to Singapore, Mr. Trump was in Canada for the G-7 summit with leaders from Canada, France, Germany, Italy, Japan and the U.K. All seven leaders had worked out a joint statement stressing the importance of a rules-based worldwide trading system.
"PM Justin Trudeau acted so meek and mild", he tweeted. But Trump's shots at Canadian prime minister Justin Trudeau and his general churlishness served no useful end. But I feel really confident", Trump said of Monday's meeting, which is the first between a North Korean leader and sitting USA president, "It's never been done, It's never been tested.
And Marc Short, the White House director of legislative affairs, said that Navarro's comments were not the words that he would have chosen to characterize the leader of Canada.
"They're both dear friends of Australia", she said.
"It is something that we have discussed and Canada is certainly prepared for any eventuality", Freeland said.
"We finished the meeting, really everybody was happy, and I agreed to sign something", Trump said.
The U.S. tariffs on Canadian imports of steel and aluminum have been set at 10% for aluminium and 25% for steel.
If the dispute can't be resolved, the two countries can take the matter to the World Trade Organisation, she said.
But the Canadian prime minister's post-conference criticism Saturday was "a betrayal" that Trump needed to respond to, to avoid showing weakness on the eve of talks with North Korean leader Kim Jong Un, he added.
International Trade Minister Francois-Philippe Champagne echoed that sentiment, saying, "We'll continue to do diplomacy the Canadian way, which is to be positive, to be constructive and to make sure we are firm to defend our industries and our workers".
As for Trump's own response, he predicted that Trudeau's remarks are going to cost Canada "a lot of money". Let us know what you think by voting in the poll above and sharing your thoughts in the comment section below.
Canadian officials have stressed the two countries' extensive trading relationship and pointed out that Canada is the top export destination for 35 US states and that 9 million jobs in the United States depend on trade with its northern neighbour.