President Donald Trump repeated his controversial claim on Thursday that the U.S. has a trade deficit with Canada to swipe at Canadian Prime Minister Justin Trudeau, a day after boasting about attempting to bluff the Canadian leader on the subject.

“We do have a Trade Deficit with Canada, as we do with almost all countries (some of them massive),” Trump said on Twitter on Thursday morning. “P.M. Justin Trudeau of Canada, a very good guy, doesn’t like saying that Canada has a Surplus vs. the U.S. (negotiating), but they do…they almost all do…and that’s how I know!”

The Office of the U.S. Trade Representative says the U.S. in 2016 had a goods and services trade surplus with Canada of $12.5 billion. And Trump’s own 2018 economic report, which was released last month and signed by the president, also notes that the U.S. runs “a net bilateral surplus only with Canada and the United Kingdom.”

But Trump and his top trade official, USTR Robert Lighthizer, argue that official statistics understate the size of the U.S. trade deficit with Canada, as well as with Mexico, because the data doesn’t reflect the value of imports from China and other suppliers that first enter the U.S. and are then re-exported to one of the North American neighbors.

“You have a number of — $30, $40, $50 billion worth — of transshipments that have nothing to do with the U.S. economy,” Lighthizer told reporters in January of this year, at the end of a round of talks to renegotiate the North American Free Trade Agreement. “We end up having wrong numbers about Canada, wrong numbers about Mexico.”

The president’s early morning tweet came after he bragged to donors at a closed-door fundraiser in Missouri on Wednesday evening that he recently told Trudeau the U.S. had a trade deficit with Canada, even though he wasn’t sure of the details. He said the Canadian prime minister refuted his claim.

“I didn’t even know,” Trump said, according to audio obtained by POLITICO. “I just said, ‘You’re wrong.’”

Trump also reportedly asked staff to check on Trudeau’s assertion that the U.S. does indeed have a trade surplus with Canada. He then said that the statistics don’t include energy and timber, “and when you do, we lose $17 billion a year,” he said. ‘It’s incredible.”

The White House defended Trump’s comments at a press briefing Thursday afternoon and appeared to embrace his formula, telling reporters that the data showing a surplus are “not complete.”

“The president was accurate because there is a trade deficit and that was the point he was making,” said White House presssSecretary Sarah Huckabee Sanders, adding: “There are plenty of things, once you take into the full account all of the trade between the two countries, that show that there actually is a deficit between those two.”

The latest back-and-forth over the deficit comes as the U.S. is negotiating with Canada and Mexico to modernize NAFTA, which took effect in 1994. Trump in recent weeks has repeatedly mentioned a U.S. trade deficit with Canada in the context of the NAFTA talks. “We have large trade deficits with Mexico and Canada,” he has said, using that to defend his argument that the agreement has been a “bad deal” for Americans.

But Canada’s Foreign Affairs Ministry, which is leading the NAFTA talks for Ottawa, brushed off Trump’s latest remarks.

“Canada and the United States have a balanced and mutually beneficial trading relationship. According to their own statistics, the U.S. runs a trade surplus with Canada,” Adam Austen, a foreign affairs spokesperson, said Thursday. “We are energetically at work modernizing and updating NAFTA to support good jobs and the middle class in Canada, the United States, and Mexico.”

Trump’s latest remarks are unlikely to have any significant effect on the ongoing talks, which are set to resume next month with another formal negotiating round, to be held outside Washington, D.C.

“I think people just look at this and say, ‘There he goes again,’” said Colin Robertson, a former Canadian diplomat who was part of the country’s original NAFTA negotiating team. “I think people think Trudeau has managed Trump well to the national interest. They know that you can’t insult him, because our prosperity depends on our ability to trade with the U.S.”

“So don’t get diverted,” Robertson added. “Don’t get fussed by this.”