He added that he had "lots of conversations with the [U.S.] president over the past weeks, and understanding as well that these tariffs were harming workers and consumers on both sides of the border".
Canada argued last summer's tariffs were illegal.
US President Donald Trump has delayed a decision on whether to impose tariffs on imports of cars and vehicle parts.
As the China tensions increased, Washington's willingness to strike a deal with Canada, the source said, became more obvious. It won't take effect until all three legislatures have voted to ratify the trade pact.
America can reimpose the tariffs if there's a surge of the products beyond historical norms. Beyond domestic use, that means massive exports and the chance of the metal entering the US through other countries even if not directly because of imports from other sources.
Canada and Mexico agreed to withdraw all complaints lodged against the U.S.at the World Trade Organization (WTO).
The US imposed tariffs on steel and aluminium last March, arguing cheap imports were an "assault on our country" that was leading to the "decimation of entire communities".
Trudeau avoided mentioning China by name - the country that the US and Canada must now carefully monitor, under the terms of the agreement, to prevent cheap foreign steel from being dumped into North America.
Spokesmen for both U.S. Steel and Nucor, that had advocated For keeping tariff protections that were powerful, couldn't be reached for comment.
Trudeau held a media availability at the Stelco steel plant in Hamilton, Ont., this afternoon where he confirmed a deal had been reached.
Foreign Affairs Minister Chrystia Freeland with Niagara Centre MP Vance Badawey on an earlier visit to Niagara.More news: Royal Duchesses Vie for Spotlight in Photo Ops After Windsor Wedding
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The Trudeau government has collected around $2 billion in counter-tariffs, but very little of that has actually gone to support our workers.
He said it was just pure good news.
US Vice-President Mike Pence said last Friday that he would meet Canada's Prime Minister Justin Trudeau in Ottawa on May 30 to discuss "advancing" ratification. "This was a real Team Canada effort".
Now, this really angered Canada in particular because it is the biggest supplier of steel to the U.S. And Canada said, you know, how can you be citing national security reasons to block our steel when we're one of your most loyal allies?
Canada has vehemently refuted those claims, with Freeland repeatedly characterizing the US position as absurd. Although the three nations agreed previous year to a new trade deal to replace Nafta, the metals and retaliatory tariffs remained in place.
The Trump administration's reluctance in exempting Canada and Mexico from the metal tariffs had frustrated the two countries during the USMCA negotiation, and was believed to be a major roadblock impeding the new deal's formal ratification.
The New Democrats criticized the Trudeau government for agreeing to the United States Mexico Canada Agreement while the tariffs remained in place, but Freeland maintained her government considered it a separate issue.
Swonger added that he hoped the latest update to the US' export deals would encourage the European Union to also withdraw its own 25% import tariff.
Meanwhile, senior U.S. Congressmen, including Sen. "Lifting these tariffs bolsters our industry, allowing us to create more jobs, drive innovation, serve customers and give back to our communities". "That's what workers asked for". Scheer told reporters he'll be looking closely at the details.
Tariffs of up to 25% on imported cars and auto parts were under consideration.
Mexico's deputy foreign minister for North America, Jesus Seade, said the U.S.