LONDON — President Trump on Tuesday slammed as “very, very nasty” and “very disrespectful” recent comments by his French counterpart about the diminished state of the North Atlantic Treaty Organization alliance.

Referring to comments President Emmanuel Macron made last month in an interview with the Economist magazine — in which Macron described the “brain death” of NATO resulting from America’s failure to consult with its allies — Trump attacked Macron on the first day of the NATO 70th-anniversary summit in London, calling the comments “very insulting.”

“You just can’t go around making statements like that about NATO,” Trump said, sitting next to NATO Secretary General Jens Stoltenberg at a one-on-one meeting between the two leaders Tuesday morning. Though Trump himself has long been a vocal critic of NATO — a combative stance that has alarmed Western allies and seemed to prompt Macron’s comments — Trump took umbrage at the French assessment of the alliance, and he depicted France as the beneficiary of American largesse.

“I would say that nobody needs NATO more than France,” Trump said. “That’s why I think when France makes a statement like they made about NATO, that’s a very dangerous statement for them to make.”

Trump tempered his rhetoric hours later, when he found himself sitting next to Macron during a pre-scheduled one-on-one meeting. There, at the Winfield House in London, where Trump is staying, the presidents still articulated their disagreements, but with a veneer of conciliation.

Trump said he and Macron had a “minor dispute” that he expected they could likely work out — a reference to France plan to tax U.S. tech giants and the U.S. threat to retaliate with tariffs as high as 100 percent on French goods.

“But we would rather not do that,” Trump said. “But it’s either going to work out or we’ll work out some mutually beneficial tax. And the tax will be substantial, and I’m not sure it will come to that, but it might.”

Macron, in his remarks, reiterated that he was not backing down from his comments to the Economist. “I know that my statements created some reactions,” Macron said. “I do stand by.”

He added: “When we speak about NATO, it’s not just about money. We have to be respectful with our soldiers. The first burden we share, the first cost we pay, is our soldiers’ lives.”

In another moment of jocular chest-thumping, Trump turned to Macron and suggested that Europe — and the French president in particular — should shoulder more responsibility for taking back captured ISIS fighters.

“Would you like some nice ISIS fighters?” Trump asked with a smirk. “I can give them to you.”

The rhetorical question prompted a scolding from Macron. “Let’s be serious,” Macron said. “A very large numbers of fighters you have on the ground are ISIS fighters coming from Syria, from Iraq and the region. It is true that you have foreign fighters coming from Europe, but this is a tiny minority of the overall problem we have in the region.”

The exchange ended with Trump teasing Macron yet again: “This is why he’s a great politician,” Trump said, “Because that is one of the greatest non-answers I’ve ever heard, and that’s okay.”

During a later meeting with Prime Minister Justin Trudeau of Canada — a NATO country that is not meeting its full financial commitment to the organization — Trump said that the leaders would be discussing what to do with “delinquent” countries, but said he personally prefers a penalty related to trade.

“I think it’s very unfair when a country doesn’t pay, so most likely I’d do something with respect to trade,” Trump said.

During three one-on-one meetings Tuesday — with Stoltenberg, Macron and finally Trudeau — Trump turned what were expected to be brief photo opportunities into his own personal daytime cable show, holding forth for a collective two hours as the other leaders largely bore witness to the U.S. president gamely fielding questions on a slew of topics.

Indeed, Trump covered issues ranging from the impeachment inquiry he is facing back home to the upcoming British elections to his thoughts on whether his secretary of state should seek a Senate seat.

In one misstep, Trump was asked if he supported the protestors in Iran, and quipped, “I don’t want to comment on that but the answer is no” — a statement at odds with his administration’s stance. Trump quickly tweeted a clarification, and also offered one at the beginning of his public meeting with Trudeau.

“We do support them totally and have supported them from the beginning,” Trump said of the Iranian protestors, adding he thought the question he was asked was about financial support.

Trump arrived in London on Air Force One and amid the swirl of impeachment; on Wednesday, the House Judiciary Committee will hold its first impeachment hearing. But one ocean and more than 3,000 miles away from the inquiry now devouring his presidency, Trump recycled some of his familiar talking points — “impeachment is a hoax,” he said — while also taking questions on the topic.

He said he did not think his position at NATO was weakened because of the inquiry, which he dismissed as a political ploy by Democrats, hoping to defeat him in the 2020 presidential election. But he added, “I think it’s very unpatriotic for the Democrats to put on a performance where they do that.”

Asked whether impeachment has cast a cloud as he tries to negotiate with other world leaders, Trump briefly turned pensive.

“Does it cast a cloud? Well, if it does, then the Democrats have done a very great disservice to the country, which they have,” he said. “They’ve wasted a lot of time.”

Trump also weighed in on the hotly anticipated Justice Department inspector general’s report about the Russia investigation due next week, claiming that he has heard from “outside” sources that it is “very powerful” and contains “a lot of devastating things.”

Turning to his host country, the president half-injected himself into Dec. 12 British elections — continuing his habit of weighing in on British politics, even though many of the country’s leaders wish he would steer clear. He said he was planning to meet with British Prime Minister Boris Johnson, but when asked why he was staying out of the British elections, he said, “I don’t want to complicate it.”

Yet several moments later, he praised Johnson — “I think Boris is very capable, and I think he’ll do a good job,” Trump said — and touted his support for Brexit. “You know that I was a fan of Brexit,” Trump said. “I called it the day before.”

The president also weighed in on whether Secretary of State Mike Pompeo should run for a Senate seat in Kansas, a state he previously represented as a House member.

“If I thought we were going to lose that seat, because we shouldn’t lose that seat . . . then I would sit down and talk to Mike,” Trump said. “But you could never find anybody that could do a better job as secretary of state.”

Asked about North Korea’s continued missile tests, Trump was sanguine, saying the country would “be in a war right now if it weren’t for me.”

“I have confidence in him,” he said, referring to North Korean leader Kim Jong Un. “I like him, he likes me, we have a good relationship.”

Still, Trump added: “He definitely likes sending rockets up, doesn’t he? That’s why I call him Rocket Man.”

As the news conference wound down, the president was asked about the decision by Prince Andrew, the second son of Queen Elizabeth II, to step back from his royal duties following a controversial interview last month about his friendship with Jeffrey Epstein, the convicted sex offender who committed suicide earlier this year.

“I don’t know Prince Andrew but it’s a tough story,” Trump said. (In fact, photos exist of Trump and Andrew together on several different occasions).

Then, after what would ultimately be his first of three impromptu news conferences, the president looked around the room and asked, “Anybody else?” Satisfied that his impromptu news conference had answered all queries, he ate breakfast with Stoltenberg before departing for a private campaign fundraiser that raised an estimated $3 million.

By the afternoon confab with Trudeau, Trump seemed to have slipped even more fully into his role as the unofficial emcee of NATO. Referring to the House Judiciary Committee hearings on impeachment, which begin Wednesday, Trump said he as going to be too busy at the summit here to take in the controversy back home.

“I’m not going to watch,” Trump said. “I’m going to be doing this. It’s much more exciting.”

Michael Birnbaum contributed to this report