Donald Trump said at an annual dinner with journalists on Saturday night (March 3) that North Korea had recently called him. Turns out, it was actually South Korea.

“They, by the way, called up a couple of days ago and said, ‘We would like to talk.’ And I said, ‘So would we, but you have to de-nuke, you have to de-nuke,’” Trump told attendees at the Gridiron Club dinner in Washington, DC.

A call from Pyongyang to the US president would have been a big deal, of course. It would have been a significant outreach (paywall) amid a tense standoff over North Korea’s development of nuclear weapons and intercontinental ballistic missiles. One of the world’s major fears of late has been war possibly breaking out on the Korean peninsula.

But the person Trump spoke with was South Korean president Moon Jae-in, reports South Korean news agency Yonhap, citing an official from the National Security Council. In the call on March 1, Moon briefed Trump on North Korea-related developments, and the leaders reaffirmed their stance that any talks with Pyongyang must have verifiable denuclearization as the goal.

It’s worth pointing out that Trump was rattling off a number of jokes in his monologue. Still, a closer look at his words seemed to suggest he was speaking seriously:

I won’t rule out direct talks with Kim Jong-un. I just won’t. As far as the risk of dealing with a madman is concerned, that’s his problem, not mine. … He must be a fine man. Do you think he’s a fine man? … Although, we did save the Olympics. President Moon gave us a lot of credit, said, ‘It was—it was president Trump that made the Olympics successful because there were a lot of people that wanted to go into that stadium with the potential of a problem—a big problem—and he gave us all a lot of credit. He said, ‘Without president Trump and his strong attitude they would have never called up and said, ‘Hey, we’d love to be in the Olympics together.’ And that’s true. … Whether people want to hear it or not, they had a very successful Olympics. That was heading for disaster. They weren’t selling tickets. … It was heading for disaster and now we’re talking. And they, by the way, called up a couple of days ago and said, ‘We would like to talk.’ And I said, ‘So would we, but you have to de-nuke, you have to de-nuke.’ So, let’s see what happens. Let’s see what happens.

It’s possible Trump was referring to South Korea when he said “they … would like to talk,” but that would make little sense, because the Moon administration can talk to the White House as necessary and because South Korea has no nuclear weapons.

It seems clear, then, that Trump believed, in the moment, that he had actually spoken to North Korea.