President-elect Donald Trump took a jab at Prime Minister Justin Trudeau on Tuesday, calling him a "governor" and referring to Canada as a "great state" — another suggestion by the incoming president that this country should be part of the United States.

Trump apparently joked about Canada becoming the 51st state during his dinner with Trudeau at Mar-a-Lago last month. In an interview with NBC News on Sunday, Trump said that if the U.S. is going to run up lopsided trade deficits with Canada, it might as well become a state.

"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 said in a social media post.

It's not clear why Trump is going public with this annexation taunt. It could be because Trudeau suggested Monday that Canada is prepared to take some sort of action against the U.S. if Trump does impose a punishing 25 per cent tariff on all Canadian imports.

"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, referring to Canada's response to Trump's tariffs on steel and aluminum in his first term.

WATCH | Feds 'determined' to defend Canada's national interest, Freeland says after another Trump jab 

Feds ‘determined’ to defend Canada’s national interest, Freeland says after another Trump jab

U.S. president-elect Donald Trump referred to Prime Minister Justin Trudeau as ‘Governor Justin Trudeau of the Great State of Canada’ in a social media post on Tuesday. That sparked a question to Chrystia Freeland, deputy prime minister and finance minister, about how to negotiate with a leader who doesn’t seem to be taking Canada seriously.

Asked about Trump's annexation remarks and whether it suggests he doesn't take Canada seriously, Finance Minister Chrystia Freeland said Canada is a great country.

"I am really clear about Canada. I know how lucky I am to be Canadian. I know what a great country we live in. And without being appropriately Canadian, nice to other countries, 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," she said.

Asked if Canada should take Trump seriously when he suggests this country may become part of the U.S., Freeland said reporters should ask the president-elect.

"I want to say to Canadians, our government is absolutely determined to defend the national interest," she said.

Immigration Minister Marc Miller dismissed Trump's comment.

"It sounds like we're living in an episode of South Park," Miller said, a reference to the American animated sitcom that has long joked about blaming Canada for U.S. troubles.

Treasury Board President Anita Anand said Canada is a "sovereign country" and the government will do what's best for Canadians in the face of Trump's threats.

"Our sole concern is the wellbeing of our country, the protection of our country, the security of our country," she said. "I am very proud to be Canadian."

She said Trump is aware of how important the bilateral relationship is because he invited Trudeau to his Florida estate.

"The very first meeting the president had with a G7 country was with Prime Minister Trudeau — that seems serious to me," she said.

Trump has said he told Trudeau at that dinner that Canada has to either harden its border to prevent migrants and drugs from coming into the U.S. or face trade action.

WATCH: Trump's concerns about drugs and the border may be really about money  

Trump’s concern about fentanyl at the border may really be about money

U.S. president-elect Donald Trump has insisted Canada needs to crack down on fentanyl flowing through the shared border. But experts say it’s not a significant problem and Trump is really looking for Canada to tighten money laundering laws.

The federal government already has announced a series of border measures, including purchases of drones and helicopters to better monitor border crossings.

Trump's allies have said Canada may have to do more to stay in his good graces and avoid the worst of his protectionist policies.

"I think it's very serious and I think one of the things that people around the world know about Donald Trump is he will follow through with things like this," said Ken Cuccinelli, who served as deputy secretary of homeland security in Trump's first term.

"While most people focus on the southern border in the U.S., the reality is, the crossings at the northern border, on a percentage basis, have gone up even faster."

WATCH | 'The president was teasing us,' says LeBlanc of Trump's '51st state' comment: 

‘The president was teasing us,’ says LeBlanc of Trump's '51st state' comment

Public Safety Minister Dominic LeBlanc, who was among the small Canadian contingent that dined with President Trump in Mar-a-Lago last week, responds to questions from reporters about Trump saying Canada could become the 51st state. LeBlanc says it was in no way a serious comment.

U.S. Customs and Border Protection (CBP) officers intercepted about 198,000 people crossing into the U.S. from Canada over the last year — a small fraction of the 2.1 million "encounters" at the southern border.

But there has been an uptick in those encounters along the northern border. Two years ago, the number of encounters was below 110,000.

An "encounter" is defined as CBP apprehending, detaining or expelling someone who has crossed into the U.S. illegally or is ineligible for entry.

On Sunday, after Trump's last Canada-U.S. taunt, Conservative Leader Pierre Poilievre said the president-elect was making these remarks because Trudeau is "weak" and Trump feels like he can take advantage of him.

"The bottom line is that Justin Trudeau is a weak leader and he gains no respect from countries all around the world," Poilievre said.

"We will go into negotiations with our American friends in a position of strength rather than weakness. Canada will be independent, strong and proud," he said.