OTTAWA – Donald Trump launched a fresh auto-tariff threat against Canada late Friday at a time when Ottawa finds itself in a holding pattern on NAFTA negotiations as it awaits the completion of one-on-one talks between the United States and Mexico.

In a tweet that appeared to reference NAFTA’s renegotiation, the U.S. president said the “deal with Mexico is coming along nicely” and that “Canada must wait.”

Trump then sent a warning to Ottawa: “Their Tariffs and Trade Barriers are far too high. Will tax cars if we can’t make a deal!”

But a spokesman for Foreign Affairs Minister Chrystia Freeland said Ottawa won’t change course in response to the president’s message.

“Our focus is unchanged,” Adam Austen wrote in an email. “We’ll keep standing up for Canadian interests as we work toward a modernized trilateral NAFTA agreement.”

Bilateral NAFTA negotiations between the U.S. and Mexico have been building momentum in recent weeks after taking a break in late May ahead of Mexico’s July presidential election. The one-on-one talks are expected to extend into next week.

Canada, however, has yet to return to the NAFTA table this summer.

Some observers have raised concerns about Canada’s absence from recent high-level negotiations on the three-country trade deal. There have been warnings Canada could be put in a position where it might have to accept a deal reached between the U.S. and Mexico.

But Canadian officials have insisted Ottawa hasn’t been sidelined during the U.S.-Mexico discussions, arguing there have been lots of bilateral talks between NAFTA partners during the yearlong renegotiation process.

To complicate matters, the already rocky Canada-U.S. relationship has deteriorated since the partners suspended talks in the spring.

Trump slapped Canada and other allies with steel and aluminum duties, which led to retaliatory levies from Ottawa. He has also made repeated threats to apply far more damaging tariffs on the deeply integrated automotive sector. And in June, Trump called Prime Minister Justin Trudeau very dishonest and weak” shortly after he left the G7 meeting in Quebec.

On Friday, his critical tweet about Canada made a point of praising Mexico’s president-elect Andres Manuel Lopez Obrador.

“New President of Mexico has been an absolute gentleman,” tweeted Trump, who also wrote that autoworkers and farmers “must be taken care of or there will be no deal.”

Earlier Friday, a source familiar with Ottawa’s NAFTA effort said Canadian negotiators would not be returning to the bargaining table in Washington until the U.S. and Mexico find common ground on their outstanding issues, especially the complex sticking points around the auto sector.

If the U.S. and Mexico can resolve their bilateral differences in the coming days, the source said it’s “very possible” Canada’s team — potentially including Freeland — could rejoin negotiations later in the week.

Media reports said Friday’s NAFTA discussions between U.S. Trade Representative Robert Lighthizer and Mexican Economy Minister Ildefonso Guajardo ended with bilateral work still to be done. On his way out of the meeting, reports said Guajardo indicated the two sides have made progress and will meet again next week to continue their talks for a fourth straight week.

“We continue to be in the same position where Mexico and the U.S. need to continue to work out their issues,” said the Canadian source, who spoke on condition of anonymity because they weren’t authorized to speak publicly about the matter.

“The next obvious question is, do we have a firm date of Canada physically going to join the talks? And the answer is no, as long as the U.S. and Mexico have not resolved their issues, specifically auto.”

The source added that Freeland and David MacNaughton, Canada’s ambassador to the U.S., remain in regular contact with relevant officials from the U.S. and Mexico.

The U.S. and Mexican governments have both expressed optimism the entire NAFTA deal could be concluded before the end of the month.

MacNaughton said in an interview last week that predictions NAFTA can be settled by the end of August are “aspirational.” However, he added that he supports the effort and that Canadian negotiators are ready to work long hours to help make it happen.

Once Canada returns to the talks, the continental partners are expected to shift their focus to other tough, unresolved issues.

MacNaughton has listed some of those stubborn areas. He said they include dispute resolution, agriculture issues, intellectual property, government procurement, the proposed inclusion of a five-year sunset clause and the de minimis threshold, which is the maximum value of an item that Canadians can order from a foreign country without paying duties or taxes.

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