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(CNN) —  

Citing insufficient progress on the issue of denuclearization, President Donald Trump nixed plans for Secretary of State Mike Pompeo to make what would have been his fourth visit to North Korea Friday, canceling next week’s trip just one day after it was announced by Pompeo.

“I have asked Secretary of State Mike Pompeo not to go to North Korea, at this time, because I feel we are not making sufficient progress with respect to the denuclearization of the Korean Peninsula,” Trump tweeted on Friday. “Secretary Pompeo looks forward to going to North Korea in the near future, most likely after our Trading relationship with China is resolved.”

Pompeo had said Thursday newly announced special representative to North Korea, Stephen Biegun, would be joining him on the trip to Pyongyang.

The top US diplomat and Andrew Kim, the head of the CIA’s Korea Mission Center, were seen entering the West Wing of the White House on Friday afternoon just hours before Trump posted the series of tweets.

Pompeo was in the room when Trump sent his tweet canceling the trip, White House press secretary Sarah Sanders told CNN.

National security adviser John Bolton, who just returned from an overseas trip, was on speakerphone, Sanders said.

A senior diplomatic source told CNN that State Department officials were “briefing allies’ embassies about their objectives for the trip like 10 minutes before” the trip was called off.

“The President’s tendency to undercut his negotiating team has made it easy for Pyongyang officials to refuse their demands. Now, as the administration finally installs a negotiating team, the President signals publicly that he doubts their ability to make progress,” Adam Mount, senior fellow and director of the Defense Posture Project at the Federation of American Scientists told CNN.

“Washington has allowed talks to drift along, unstable, unproductive, and without a coordinated negotiating team. It appears the President is willing to allow this to continue into the fall,” he said.

A diplomatic source told CNN that while it is possible that high-ranking officials in Seoul were informed of Trump’s decision to cancel the trip prior to the tweets, the announcement caught South Korean diplomats at the working level off guard. South Korean President Moon Jae-in plans to visit Pyongyang next month for a third summit with Kim.

“The decision also leaves Moon Jae-in isolated ahead of his planned trip to Pyongyang next month. Both Seoul’s approach on economic and threat reduction and the US nuclear talks would benefit from being integrated,” Mount said.

The South Korean Foreign Ministry said Foreign Minister Kang Kyung-hwa and Pompeo spoke by telephone Saturday to discuss the canceled trip and where negotiations might go from here.

A statement released by the ministry said Pompeo explained “in detail” the reasons for postponing the trip. The statement did not elaborate.

According to the South Korean Foreign Ministry, Kang called the cancellation “regrettable” while Pompeo reaffirmed the US position that it will continue to solidify South Korea-US cooperation.

On Friday, Trump specifically referenced the ongoing tariffs battle between the US and China as part of the reason for the lack of progress on North Korean denuclearization, something he has previously hinted at.

“Because of our much tougher Trading stance with China, I do not believe they are helping with the process of denuclearization as they once were (despite the UN Sanctions which are in place),” Trump said in one of three tweets Friday afternoon on the issue.

Trump was asked in an interview with Reuters on Monday if North Korea had done anything beyond dismantling a test site to show it was in the process of denuclearizing. “I do believe they have,” he said, but did not provide further details.

Despite the cancellation, Trump sent his “warmest regards and respect” to North Korean leader Kim and said he looks “forward to seeing him soon!”

When the two leaders met in Singapore in June, Trump praised the young autocrat, saying Kim had “to be a rough guy,” but that he’s “smart, loves his people, he loves his country. He wants a lot of good things and that’s why he’s doing this.”

State Department spokesperson Heather Nauert said Thursday that there were “no plans for a meeting” between Pompeo and Kim on the trip.

Kim snubbed Pompeo during the last round of meetings in North Korea early last month, which sources told CNN went “as badly as it could have gone.”

Diplomatic sources said that the US has now presented North Korea with specific proposals for a path and timeline to denuclearization, all of which Kim has thus far rejected, believing the US’s stance to be “gangster-like.”

The latest assessment of North Korea’s nuclear program released by the International Atomic Energy Agency calls into question Pyongyang’s commitment to denuclearization amid ongoing activities at certain sites in the country and the inability for IAEA inspectors to access those sites. The report cites “cause for grave concern” about these activities.

And, according to the prominent monitoring group 38 North, commercial satellite imagery from Aug. 16 of the Sohae Satellite Launching Station, North Korea’s only operational space launch facility, indicates that no significant dismantlement activity has taken place at either the engine test stand or the launch pad since Aug. 3.

Last month, 38 North released images of the Sohae station, prompting Trump to say North Korea had begun dismantling “a key missile site.”

But according to the group’s most recent analysis, “no new dismantlement activity is apparent since August 3.”

CNN’s Sophie Jeong in Seoul, and Kaitlan Collins, Elise Labott and Michelle Kosinski contributed reporting.