After President Trump met with North Korea’s Kim Jong Un in Singapore this week, the two leaders agreed to "work toward complete denuclearization of the Korean Peninsula."

However, they did not announce exactly how they would do so; the document they signed, less than 400 words long, had few practical details about how North Korea would actually get rid of its nuclear weapons.

To some observers, this is a major problem. But Secretary of State Mike Pompeo does not want to hear the criticism.

Speaking at the Hilton Hotel in Seoul on Wednesday, Pompeo was asked whether North Korea’s denuclearization would be "verifiable and irreversible" — a phrase that the secretary has used in describing what the United States saw as an acceptable way for North Korea to get rid of its weapons.

Here’s how Pompeo responded, according to a State Department transcript:

QUESTION: Mr. Secretary, I wanted to ask you about “verifiable and irreversible.”
QUESTION: You said — the day before you said it’s our only objective, our — it’s clear we want that. It’s not in the statement. Why it’s not in the statement? And the president said it will —
SECRETARY POMPEO: Mm-hmm, it’s in the statement. It’s in the statement. You’re just wrong about that.
QUESTION: How is it in the statement? And I am also —
SECRETARY POMPEO: You’re just — because “complete” encompasses verifiable and irreversible. It just — I suppose we — you could argue semantics, but let me assure you that it’s in the document.
QUESTION: And the president said it will be verified.
SECRETARY POMPEO: Of course it will.
QUESTION: Can you tell us a little bit more about —
SECRETARY POMPEO: Of course it will. I mean —
QUESTION: — what is — what discussed about how?
SECRETARY POMPEO: Just so you know, you could ask me this — I find that question insulting and ridiculous and, frankly, ludicrous. I just have to be honest with you. It’s a game and one ought not play games with serious matters like this.
QUESTION: But how will it be verified? Did you discuss that? Do you have —
SECRETARY POMPEO: Oh, we’re — they’re — the modalities are beginning to develop. There’ll be a great deal of work to do. It’s — there’s a long way to go, there’s much to think about, but don’t say silly things. No, don’t, don’t. It’s not productive. It’s not productive to do that, to say silly things. It’s just — it’s unhelpful.
QUESTION: Well, I think —
SECRETARY POMPEO: It’s unhelpful for your readers, your listeners, for the world. It’s — because it doesn’t remotely reflect the American position or the understandings that the North Koreans have either.
QUESTION: We’re just trying to understand how it reflects what you asked that —
SECRETARY POMPEO: Yeah, and I just articulated that for you.

In his remarks, Pompeo suggests that though the words “verifiable” and “irreversible” do not appear in the agreement reached by Trump and Kim, they are implied in the word “complete” in the third point the pair agreed to: “Reaffirming the April 27, 2018, Panmunjom Declaration, the DPRK commits to work toward complete denuclearization of the Korean Peninsula.”

In the past, U.S. officials have repeatedly spoken of the need for “complete, verifiable and irreversible dismantlement” of North Korea’s nuclear weapons program — a term so widely used that it has its own abbreviation, CVID.

Neither the United States nor North Korea has spoken publicly about how Pyongyang’s denuclearization would meet that standard.

Though North Korea took the unilateral move of demolishing a key nuclear weapons testing site last month, it did so without the presence of international, expert observers at the scene. Some experts have their doubts that any denuclearization process initiated by Pyongyang could realistically meet a standard of “irreversible.”

“Nobody is suggesting that North Korean nuclear scientists leave the country or they be shot,” Robert Galluci, a former U.S. negotiator with Pyongyang, told the Korean Times last month. “Anything that has been built and has been dismantled can be built again.”

Though the rest of his news briefing in Seoul was less contentious, Pompeo returned to the idea that critics were misunderstanding the nature of the agreement a number of times. Noting that he himself had met with Kim and other North Korean officials multiple times, he said he was “confident they understand that there will be in-depth verification.”

Pompeo also acknowledged that while the Trump-Kim statement was brief, there was more work being done behind the scenes.

“Not all of that work appeared in the final document, but lots of other places where there were understandings reached,” he said. “We couldn’t reduce them to writing, so that means there’s still some work to do, but there was a great deal of work done that is beyond what was seen in the final document that will be the place that we’ll begin when we return to our conversations.”

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