Donald Trump promised an absent Prime Minister Justin Trudeau some in-person presidential face time Wednesday as the U.S. commander-in-chief and his Mexican counterpart went ahead celebrating North America’s new trade deal without Canada.

Trudeau last week declined to join Trump and Mexico’s President Andres Manuel Lopez Obrador at the White House, citing the challenges of the ongoing COVID-19 pandemic and this week’s pressing parliamentary business — not to mention the looming threat of renewed U.S. tariffs against Canadian aluminum exports.

Trump offered no hint of any such tensions before he and Lopez Obrador signed a joint declaration of solidarity during an outdoor Rose Garden ceremony under a sweltering summer sun.

Instead, “we’ll have a separate day with Canada — they’re coming down at the appropriate time,” the president said, declaring the U.S.-Mexico-Canada Agreement, or USMCA, the “largest, fairest and most advanced” trade deal ever signed, and deriding its NAFTA predecessor as precisely the opposite.

“We want to thank Canada also; I spoke with and will be speaking to the prime minister in a little while,” Trump said. “We want to congratulate Canada, and the people of Canada, and the prime minister.”

Earlier Wednesday, Trudeau extended congratulations of his own, calling the agreement a win for all three countries at a time of serious economic uncertainty.

“I think it’s really important that at a time of economic strain and stress that we continue to have access to the world’s most important market. This is good for Canadian workers and Canadian jobs right across the country.”

The formal debut of the agreement, which took effect last week, has nonetheless been sullied by the U.S. trade representative’s claim that Canada has exceeded limits on aluminum exports to the United States established when Trump lifted national-security tariffs on Canadian-made steel and aluminum in May 2019.

Trump made no mention of the latest dispute in his Rose Garden remarks, and neither leader took questions. Trudeau, however, said the threat of renewed tariffs “is a little bit difficult to understand,” given the potential impact of such a move.

“The U.S. doesn’t make nearly enough aluminum to be able to cover its needs, particularly at a time when we want economies to get going again across North America,” he said in Ottawa. “What tariffs would do would be to raise prices for manufacturers in the United States and put extra stresses on them at a time when stresses abound.”

Higher prices may be precisely the goal: the two U.S. producers that are urging the USTR to take action have ties to a Swiss metals company that holds the exclusive rights to sell Russian-made aluminum in the United States. China, Russia, India and Canada are the four largest aluminum producers in the world.

Lopez Obrador’s visit to Washington, his first foreign trip since being elected in 2018, has prompted widespread criticism at home for a leader whose campaign trafficked heavily in criticizing Trump. Since then, the leader known in Mexico as AMLO has been pilloried for his deference to a U.S. president famous for aggressive anti-immigration policies at the southern border.

With a U.S. presidential election now just four months away, it’s Trump who stands to benefit politically from a bilateral visit, experts told a Wilson Center panel discussion Wednesday — and if Lopez Obrador hopes to secure safe harbour from Trump’s unpredictable foreign-policy whims, he may be sadly mistaken.

“If he thinks that going to Washington in this moment … is going to insulate him or protect him from future actions by this president, especially in a campaign year — against tariffs, against some kind of other punitive measure — I think he’s fooling himself,” said Roberta Jacobson, a former U.S. ambassador to Mexico under both Trump and his predecessor Barack Obama.

“Witness the fact that obviously we have the discussion of aluminum tariffs vis-a-vis Canada right now, as we’re celebrating USMCA. This is not a president who necessarily says, ‘These are my new partners, I will not penalize them no matter what.”‘

Conservative Leader Andrew Scheer made a similar point, but not without twisting the partisan knife a little.

“Usually when Justin Trudeau leaves the country, it hurts Canada’s position on the world stage, so maybe it’s a good thing he stayed home,” Scheer said. “He has a perfect losing record when it comes to Donald Trump, so maybe we’re better off that he didn’t go.”

New Democrat trade critic Daniel Blaikie, meanwhile, is urging the federal Liberal government to spell out during a House of Commons trade committee meeting Thursday how it plans to protect Canada’s aluminum sector from the threat of an “arbitrary attack.”

“A second tariff levelled at an industry that is already hurting could very well be devastating,” Blaikie wrote in a letter this week to International Trade Minister Mary Ng. “The current global pandemic only makes matters worse.”