Amid a looming tariff threat, U.S. president-elect Donald Trump appears to be mocking Prime Minister Justin Trudeau, referring to him as "Governor Justin Trudeau" in a post on Truth Social early Tuesday.

"It was a pleasure to have dinner the other night with Governor Justin Trudeau of the Great State of Canada. I look forward to seeing the Governor again soon so that we may continue our in depth talks on Tariffs and Trade, the results of which will be truly spectacular for all!" Trump wrote.

Trump's remark comes hours after Trudeau said Canada will respond if the U.S. moves ahead with a 25 per cent tariff on Canadian imports unless Canada addresses Trump's border concerns.

"We will, of course, as we did eight years ago, respond to unfair tariffs in a number of ways, and we're still looking at the right ways to respond," Trudeau said at a fireside chat with the Halifax Chamber of Commerce on Monday.

While Trudeau acknowledged this latest threat is "more challenging" and the economic impact of the tariffs would be "devastating," the prime minister also appealed for calm, saying "not to panic."

"Knowing that yes, (the tariffs) would be absolutely devastating means we have to take them seriously, but it does mean we have to be thoughtful and strategic, not go around making our opponents' arguments for him, but making our arguments in a significant and united way," Trudeau said.

Tuesday’s Truth Social post is Trump’s latest jab at Trudeau.

Less than two weeks ago, Trudeau – along with his chief of staff Katie Telford and Public Safety Minister Dominic LeBlanc– made a surprise visit to Mar-a-Lago to have dinner with Trump and members of his incoming administration to discuss the tariff threat.

Following the meeting, U.S. network Fox News reported Trump joked during the dinner in Florida that if said tariffs debilitated the Canadian economy — as the prime minister conveyed to him — perhaps Canada should become America's 51st state.

Canadian politicians later downplayed the joke, with LeBlanc saying, "The president was teasing us." 

Justin Trudeau Donald Trump Mar-A-Lago

Meanwhile, in an interview with CTV News Channel's Power Play last week, Canada's Ambassador to the U.S. Kirsten Hillman described the comment as "reassuring."

"(Trump) made jokes, other people at the table made jokes," Hillman said, who was part of the Canadian delegation to Mar-a-Lago, though she wasn't seated at the same table as Trump and Trudeau during the three-hour dinner. "People were making jokes, which, actually, I have to say, I find to be reassuring that people are that comfortable with each other, that they're teasing."

But following that meeting, two senior government sources told CTV News that it was conveyed to the Canadian delegation the tariffs are unavoidable in the immediacy, but solutions in the longer term are on the table, particularly if the border is better secured.

Days after the meeting, Trump posted an A.I.-generated image to social media that depicted him standing next to a Canadian flag and overlooking a mountain range with the caption “Oh Canada!”

Meanwhile, in his first post-election interview, Trump doubled down on his tariff threat, calling the measure "beautiful."

"I'm a big believer in tariffs. I think tariffs are the most beautiful word. I think they're beautiful. It's going to make us rich," Trump said in an interview with NBC's Meet The Press that aired Sunday.

Trump also made reference to Canada becoming a U.S. state.

"We're subsidizing Canada to the tune over $100 billion a year. We're subsidizing Mexico for almost $300 billion. We shouldn't be — why are we subsidizing these countries?" Trump said. "If we're going to subsidize them, let them become a state."

In that interview, the U.S. president-elect later reiterated his border concerns.

"We can't have open borders. And I said to the president of Mexico and to Justin Trudeau, if it doesn't stop, I'm going to put tariffs on your country at about 25 per cent," Trump said.

In the wake of the tariff threat, the federal government says it will be adding more personnel and equipment resources at the border but so far has yet to outline specifics.

How is Ottawa responding to Trump's 'Governor' remark?

Deputy Prime Minister and Finance Minister Chrystia Freeland is leading Canada's revived committee on Canada-U.S. relations.

Asked on Tuesday about Trump's remarks and whether he takes Canada seriously, Freeland said Canada is a "great country."

"I want to say Canada is the greatest country in the world. I'm very clear on that. All of us are very clear on that," Freeland said.

And when asked directly if she thinks Trump is "trolling the federal government," Freeland said she urges "everyone who has questions to the president-elect to pose those to him."

Speaking to reporters outside Tuesday's Liberal cabinet meeting, several ministers referred to Trump's remark as a "joke."

"It sounds like we're living in an episode of South Park," Immigration Minister Marc Miller said, adding later, "I don't think we should necessarily be looking at Truth Social for public policy."

Defence Minister Bill Blair also quickly responded, saying, "I don't take offence at jokes."

Health Minister Mark Holland, meanwhile, said that Canada needs to have a "mature" response.

"We have to all not react to every word because we don't know the context," Holland said.

Will Canada retaliate?

Prior to Trudeau’s comments on Monday that Canada will “respond to unfair tariffs,” other federal government officials have said retaliatory measures were being put together.

“We'll be prepared, as we have to be, to take measures in retaliation,” Hillman said to CTV News last week. “I hope that we don't have to get there.”

During his first term as U.S. president, Trump in 2018 triggered a nearly yearlong trade war imposing a 25 per cent tariff on Canadian steel products and 10 per cent on Canadian aluminum. In response, Canada unveiled a 25 per cent counter tariff on a long list of American steel and aluminum products, along with a 10 per cent surtax on miscellaneous U.S. goods including coffee, prepared meals and maple syrup. Those retaliatory tariffs were eventually lifted in 2019 after Canada, the U.S. and Mexico reached a deal.

Trump once again announced plans to impose a 10 per cent tariff on Canadian aluminum in August 2020, but later hit pause amid the looming presidential election later that year.

New poll says 13 per cent of Canadians think Canada should become 51st state

According to a new poll from Leger, 13 per cent of Canadians would like the country to become the 51st state of the United States, while 82 per cent oppose the idea. 

The poll also shows there’s higher support among men, at 19 per cent, compared with only seven per cent of women.

In terms of party breakdown, 21 per cent of Conservative party supporters agreed with the idea, along with 10 per cent of Liberal and six per cent among the NDP. The People’s Party of Canada showed the highest level of endorsement among the federal parties, at 25 per cent.

With files from CTV News' Spencer Van Dyk