President Trump doesn’t mince words. Not with voters, not with the media, and not with foreign leaders.

The president is in London this week for NATO meetings, a cup of tea with some British royalty and a slew of bilateral meetings with some prominent foreign heads of state. And he’s already making headlines.

Before Trump arrived, French President Emanuel Macron took a shot at the North Atlantic Treaty Organization, an intergovernmental military alliance between 29 North American and European countries.

“What we are currently experiencing is the brain death of NATO,” Macron told The Economist magazine, referring to Trump’s decision to withdraw troops from northeastern Syria. He said the U.S. appears to be “turning its back on us.”

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Trump fired back.

“I heard that President Macron said that NATO is brain dead and I think that’s insulting to a lot of different forces, including a man that does a very good job at running NATO. It has a great purpose, especially with the fact that NATO is becoming much more flexible in terms of what it looked at,” Trump said.

“It’s a tough statement. When you make a statement like that, that is a very, very nasty statement to essentially, including them, 28 countries.” And Trump added: “Nobody needs NATO more than France, if you just look back over the last long period of time. … 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.”

Then Trump and Macron met face to face.

It didn’t go well for Macron.

In a tense exchange, Trump whacked Macron, asking him if he’d like to take back “some nice ISIS fighters” — and then hit him again for his “non-answer.”

“I have not spoken to the president about that — would you like some nice ISIS fighters?” he asked Macron, when asked about ISIS fighters from Europe captured in Syria. “I can give them to you, you can take every one you want.”

Macron dodged the question in a rambling answer in which he told Trump “be serious.”

Trump didn’t like that.

“This is why he’s a great politician, because that’s one of the greatest non-answers I’ve ever heard,” Trump said.

Ouch.