"The impact on Canada and ultimately on workers in the USA won't be a laughing matter", one source told the network.
In 2017, it was the second-largest importer of USA steel and steel products, which will now face an additional 25 percent tariff, in line with what the US has imposed. Some further tariffs will come into force on July 5. The US has a massive trade deficit with China.
Canada countered by announcing it would slap an estimated $16.6 billion in duties on some steel and aluminum products and other goods from the USA, including maple syrup, beer kegs, whisky and toilet paper.
The tariffs are meant to negatively affect areas of the country that supported President Donald Trump in 2016.
The G7 summit on Friday and Saturday in La Malbaie, a small town 140 kilometers (87 miles) from Quebec City, will bring together the leaders of Britain, Canada, France, Germany, Italy, Japan and the United States.
The comments by the two leaders at a Parliament Hill news conference before they each departed to Charlevoix for the summit laid bare the frustrations and even anger at Trump's policy decisions.
The list includes whisky, cheese, steel, bourbon, and pork. Mexico sells about 80% of its exports to the US.
Trudeau described the tariffs as "unilateral and illegal" and the national security pretext as "risible".
In the case of the United States, the subsequent embargo caused economic decline in the short run, even though it's being credited with making the United States more self-reliant in the long term.
The reports do not say what types of penalties are being looked at.
What are tariffs? Taxes on products made overseas. That will also possibly mean increased supply in the USA domestic market, leading to a reduction in prices in supermarkets, but farmers are likely going to be an unhappy lot.
"Japan and the European Union will team up on this issue and call on cooperation from other countries", Japanese Trade Minister Hiroshige Seko told reporters Tuesday.
However, one Mexican producer disagrees with Hernández's assessment that pork prices won't rise.
Trudeau said he has been "blunt" in private conversations with Trump and said the two-day G7 gathering is a chance for more "frank" discussions. Now the G7's future is in doubt, with Trump's imposition of steel and aluminum tariffs on his G7 partners, as well as broader disagreements on the trade and climate change.
"In no way is this [tariff list] publication revenge". The United States has the lowest average tariff in the world.
Mexico has been a valuable trade partner, as it has become a significant source of US imported crude oil.
"NAFTA has kind of dragged on", Kudlow said of the negotiations.
The EU has also announced new duties in response.
"Canada's position is, and always has been, that the tri-lateral approach is actually better for Canada, for Mexico, and for the United States".