President Donald Trump wasted little time this week firing back at Canadian Prime Minister Justin Trudeau after he was caught on a hot mic video.

During a reception Tuesday night at Buckingham Palace in London, Britain Prime Minister Boris Johnson asked French President Emmanuel Macron: “Is that why you were late?”

Trudeau mockingly said: “He was late because he takes a 40-minute press conference off the top.”

Trudeau was referring to an unscheduled Q&A by Trump, where he spoke to reporters for quite awhile about a myriad of topics.

“You just watched his team’s jaws drop to the floor,” Trudeau added, insinuating Trump’s team was embarrassed of his press conference.

WATCH:

.@JustinTrudeau, @EmmanuelMacron, @BorisJohnson and other VIPs shared a few words at a Buckingham Palace reception Tuesday. No one mentions @realDonaldTrump by name, but they seem to be discussing his lengthy impromptu press conferences from earlier in the day. (Video: Host Pool) pic.twitter.com/dVgj48rpOP — Power & Politics (@PnPCBC) December 3, 2019

When Trump appeared alongside Germany Chancellor Angela Merkel on Wednesday morning, the president was asked about Trudeau’s comments.

Needless to say, Trump was visibly not happy about it and blasted Trudeau as being “two-faced.”

“Well, he’s two-faced. And honestly with Trudeau, he’s a nice guy. I find him to be a very nice guy,” Trump began.

“The truth is I called him out on the fact that he’s not paying 2%, and I guess he’s not very happy about it,” he continued. “He’s not paying 2%, and he should be paying 2%. It’s Canada, they have money, and they should be paying 2%. So I called him out on that, and I’m sure he wasn’t happy about it. But that’s the way it is.”

Trump described Canada as “slightly delinquent on defense spending” on Tuesday before Trudeau’s comments and said twice that Trudeau provide his country’s current defense spending figure as a proportion of GDP.

Asked about German spending ahead of their meeting, Trump said: “Well, Germany’s a little bit under the limit, I will say that, but we’ll talk about that now.”

WATCH:

“Well, he's two-faced. And honestly with Trudeau, he's a nice guy. I find him to be a very nice guy, but the truth is I called him out on the fact he’s not paying 2%,” said @POTUS after @JustinTrudeau’s candid comments caught on camera. https://t.co/8E8xgJGqVR #cdnpoli pic.twitter.com/xtftsBTa6k — Power & Politics (@PnPCBC) December 4, 2019

Trump has been railing against NATO for years and demanding other nations in the organization pay their fair share.

While NATO leaders are meeting this week in London, the alliance said Thursday it had agreed to redistribute costs and cut the U.S. contribution to its central budget.

Beginning in 2021, both U.S. and Germany will contribute about 16 percent.

Trump has been understandably ticked off that only 9 of the 29 member countries are meeting the 2 percent gross domestic product target for the alliance’s defense spending.

All NATO states are required to pay at least 2 percent of its GDP to account for defense spending.

A vast majority of the NATO states have been delinquent and not meeting their financial obligations, and Trump has been calling them out to their faces over this.

Trudeau said Canada is paying around 1.4 percent — which is nowhere close to the 2 percent they are required to pay.

The United States currently pays around a whopping 22 percent of NATO’s central budget.

Beyond Trump pressing NATO members to pay their fair share and stop relying on America to foot the bill, Trudeau’s comments are very revealing.

When he’s face-to-face with Trump, he shakes his hand, smiles, and has nothing but nice things to say.

But when Trump’s not around, Trudeau apparently thinks he’s a tough guy who can bad mouth America — a nation that’s supposed to be a top ally to Canada.