WASHINGTON – President Donald Trump on Monday touted a new trade agreement brokered with Canada and Mexico as "truly historic news."

"The agreement will govern nearly $1.2 trillion in trade, which makes it the biggest trade deal in United States history," Trump said during remarks in the Rose Garden.

"It puts us in a position we've never been in before," he said. "This is a terrific deal for all of us."

Speaking to reporters in Ottawa, Canadian Prime Minister Justin Trudeau, who has argued with Trump over trade in recent months, said the new deal “will be good for Canadian workers, good for Canadian businesses and good for Canadian families.”

Reaching the agreement “was no easy task,” Trudeau said, and the work isn’t done yet because the pact still must be ratified by all three countries.

But free and fair trade “is in a much more stable place than it was yesterday,” the prime minister said. “We now have a path forward.”

Asked if the agreement would help repair his fractured relationship with Trump, Trudeau said he had “a very positive call” with the American president Monday morning.

There is no question that renegotiating NAFTA has been a challenge in his conversations with Trump, Trudeau said. But with the trade talks now out of the way, “we will continue to work on things that allow us to benefit our workers, benefit our citizens and take on the world together as a North American market,” he said.

“We celebrate a trilateral deal. The door closes on trade fragmentation in the region,” tweeted Jesús Seade, trade negotiator for Mexico’s incoming president, Andrés Manuel López Obrador.

U.S. and Canadian officials announced the new deal overnight. The U.S. had imposed a deadline of midnight Sunday with Canada to reach a new three-country deal that covers a North American market of nearly 500 million consumers.

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The new trade deal, which must be approved by Congress, is designed to replace the North American Free Trade Agreement, which Trump has denounced as unfair to the United States. The new agreement includes new rules for the movement of products between the three countries, and even a new name.

Earlier Monday, Trump tweeted that "the new name [of NAFTA] will be The United States Mexico Canada Agreement, or USMCA."

Trump returned to the name during his remarks on Monday. "It has a good ring to it," he said.

Trump said his tariffs were the reason for the deal, and he described opponents as “babies." He said he hoped the deal would be quickly approved by Congress but warned that he never knows for sure what lawmakers will do.

“In theory there should be no trouble,” Trump said. "I think it’ll pass easily, really easily, because it’s a great deal."

In a briefing with reporters following the president's news conference, U.S. Trade Representative Robert Lighthizer said the new trade agreement with Canada makes improvements in a number of areas, including rules or origin for automobiles, labor provisions, intellectual property, access to agricultural markets, and the new review mechanism.

Those are also the reasons that this agreement is much better than the United States would have gotten from Canada and Mexico under the dormant Trans-Pacific Partnership, said Lighthizer, who emphasized that it "is substantially better than the TPP."

White House adviser Jared Kushner, who is the president's son-in-law, praised both the president and Lighthizer, saying the deal “will make a big difference for this country.”

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