Speaking at a news conference Thursday, the normally mild-mannered young prime minister expressed particular dismay that the tariffs announced by the Trump administration were being imposed on national security grounds to protect the US economy and vital industries.
Also, the Prime Minister rejected the idea that Canadian steel contained in USA military vehicles or the aluminum, used in its combat airplanes, in some way represents any threat.
Ministers urged the U.S.to quickly abandon the tariffs ahead of the leaders' summit before the move causes deeper divisions within the G7.
U.S. Treasury Secretary Steven Mnuchin failed to soothe the frustrations of his Group of Seven counterparts over the 25 percent steel and 10 percent aluminum tariffs that Washington imposed on Mexico, Canada and the European Union this week.
He made the comment while outlining Canada's response to US tariffs on steel and aluminum imports.
Trudeau was in Halifax to speak to the annual conference of the Federation of Canadian Municipalities.
The announcement came as Ottawa and Mexico City announced they were retaliating against steep metal tariffs imposed Friday and Washington faced a barrage of complaints at a finance ministers summit in Canada.
As tariff battles commence and a new NAFTA deal has yet to take shape, Canada's limits as the kind neighbour are being tested, the prime minister said.
He says that while they may be longtime allies of the USA, they have been taking economic advantage of Americans for far too long. "Do you really believe that Canada, that your North Atlantic Treaty Organisation allies, represent a national security threat to you?"
"The fact that the president has moved forward with these tariffs is not just going to hurt Canadian jobs".
Only 24 hours after he applied hefty tariffs on Canadian steel and aluminum, President Trump described for the first time how he envisions the future of NAFTA.
Identical tariffs were also placed on imports from Mexico and the European Union.
Mexico says it will answer tariffs on steel and aluminum announced by the Trump administration with duties of its own on a variety of United States of America products, including pork bellies, apples, grapes, cheeses and flat steel among other things.
The US was on Saturday singled out by some of its closest allies over the imposition of tariffs that they warn would undermine open trade and weaken confidence in the global economy. "We're also putting a number of tariffs on consumer goods, finished products for which Canadians have easy alternatives". "It can be solved if people work together", Kudlow said.
Trudeau said that the United States has a $2bn billion surplus on steel with the U.S., and was "very much aligned" on the issue of China.