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WASHINGTON (AP/KDKA) – President Donald Trump is announcing a trade “understanding” with Mexico that could lead to an overhaul of the North American Free Trade Agreement.

Trump made the announcement Monday in the Oval Office, with Mexican President Enrique Pena Nieto joining by speakerphone.

Canada, which is part of NAFTA, is not participating in the announcement. Trump says negotiations with Canada have yet to begin and is calling on the country to negotiate fairly. He’s threatening anew to slap tariffs on Canadian cars if they fail to do what he wants.

Trump says the call is being held to “celebrate the understanding” the U.S. and Mexico have reached on trade.

He says, “It’s an incredible deal for both parties.”

Republican Sen. Pat Toomey released a statement Monday evening on the administration’s announcement. It reads in part:

“The administration’s contention that the agreement improves market access for dairy farmers, and strengthens intellectual property rights, is encouraging. Nevertheless, I continue to have serious concerns about an arbitrary wage mandate for the auto sector, any weakening of protections for U.S. investors, and an automatic self-termination of the agreement after a specified period of a time. Such a “sunset” provision would discourage trade and investment, as well as set the wrong precedent for future agreements.”

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