President Trump stops to talk to reporters and members of the media as he walks from the Oval Office to board Marine One on the South Lawn of the White House on Wednesday. (Jabin Botsford/The Washington Post)

The United States might accept a “phase-in” of North Korea’s denuclearization but the dismantling of Kim Jong Un’s nuclear program must progress “rapidly,” President Trump said in an interview broadcast Thursday.

“We’re going to see. I’d like to have it done immediately,” Trump said on “Fox & Friends” on Fox News. “But, you know, physically, a phase-in may be a little bit necessary, we will have to do a rapid phase in, but I’d like to see it done at one time.”

Trump’s comments, which were taped Wednesday, came as North Korea threatened to reconsider participation in a summit with Trump next month in Singapore. Trump wants to negotiate an end to the North’s possession of nuclear weapons.

North Korea said Wednesday that it is up to the United States to decide whether it wants to “meet us at a meeting room or encounter us at nuclear-to-nuclear showdown.”

A close aide to Kim unleashed a torrent of invective against the Trump administration Thursday morning, calling Vice President Pence a “political dummy” for remarks he made Monday in a television interview that made reference to the downfall of the late Libyan leader Moammar Gaddafi.

North Korea bristles at Trump administration suggestions that it follow the “Libyan model” to abandon its nuclear efforts. Gaddafi was killed in 2011 during anti-government chaos.

During Trump’s interview, he continued to hedge on whether the meeting with Kim, scheduled for June 12, will take place.

“We’ll see what happens,” he said. “Right now we’re looking at it, we’re talking about it. And they’re talking to us. We have certain conditions. We’ll see what happens.”

“But there’s a good chance,” Trump added. “I mean it’ll be a great thing for North Korea. If that happens, it would be a great thing for North Korea. Most importantly it would be a great thing for the world, so we’ll see what happens.”

Anna Fifield in Tokyo contributed to this report.