"The idea that the Canadian steel that's in military, military vehicles in the United States, the Canadian aluminum that makes your, your fighter jets is somehow now a threat?" he continued.
"Were the United States to be successful it sets a precedent for others do the same and to use national security as pretext for protectionism, and secondly, it leads the WTO into the realms of having to determine what is and what is not acceptable as a definition for national security, something the WTO has always shied away from".
In Canada, Trudeau announced what he called "directly reciprocal" tariffs targeting USA products like steel and toilet paper.
"No president has fought the war on poverty better than Donald J. Trump", Mr. Navarro said on Fox's "Sunday Morning Futures".
Beijing pledged any tariffs on their goods would nullify any trade deal reached between the USA and China.
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Weinstein has been accused of sexual misconduct - including harassment, assault, and rape - by more than 80 women since last fall. Harvey Weinstein , center, listens during a court proceeding in NY during his arraignment on rape and other charges on May 25.
Canada retaliated against the latest punitive measures last week by proposing levies on C$16.6 billion worth of USA exports that would take effect on July 1.
Canada has already granted some access to its dairy markets in its other big free trade deals with the European Union and the re-booted Trans-Pacific Partnership, the 11-country Pacific Rim pact that does not include the U.S.
Trump "is responding to several decades of trade abuses here" and will continue to defend USA interests, Kudlow said. "But we see no sign of that in this action today by the United States administration", the prime minister said.
Joseph Galimberti, president of the Canadian Steel Producers Association, speaks to reporters after a meeting with Prime Minister Justin Trudeau on Parliament Hill in Ottawa on Monday, June 4, 2018. "And on top of that, these tariffs are going to be hurting American workers and Canadian workers", he added.
In a statement issued by Canada, the G7 finance officials agreed that "decisive action is needed" on the tariff issue at a summit of G7 leaders next week in Charlevoix, Quebec. "We're that interconnected, so we want a win/win, and that's what we've been working toward". "At the same time, the Trump Administration's actions underscore its commitment to good-faith negotiations with our allies to enhance our national security while supporting American workers".
Finance chiefs from the group of wealthy nations emerged from three days of talks on Saturday "unanimous" in their condemnation of Trump's decision to impose tariffs on steel and aluminum, promising to press ahead with retaliatory measures unless Trump steps back.