SEOUL >> Kim Yong Chol, a former North Korean spy master and vice chairman of its ruling Workers’ Party, had been the country’s most internationally visible diplomat in the past year, visiting the White House twice and leading negotiations for North Korean leader Kim Jong Un’s two summit meetings with President Donald Trump.

Now, he has suddenly become the latest example of how a senior North Korean official’s political fortune is made or broken at the whims of Kim Jong Un. This week, leading South Korean newspapers reported Kim Yong Chol’s fall from grace. One of them, the conservative daily Chosun Ilbo, went so far as to report that Kim had been banished to forced labor, with many of his negotiating team members either executed or sent to prison camps.

South Korean officials and analysts cautioned that it was too early to say with precision what was happening inside Kim Jong Un’s opaque regime. South Korean news media offered differing conjectures, including whether Kim Hyok Chol, the North’s special nuclear envoy to the United States, had been executed by firing squad in March, as the Chosun Ilbo reported, or was still under interrogation.

But they all agree on one thing: Kim Yong Chol and his negotiating team, which had driven Kim Jong Un’s diplomatic outreach toward Washington, have been sidelined, as the North Korean leader sought a scapegoat to blame for his disastrous second summit meeting with Trump, held in Hanoi, Vietnam, in February.

Kim Yong Chol, 73, and his senior team members — including the special envoy Kim Hyok Chol and Kim Song Hye, both of whom accompanied Kim Yong Chol when he visited Trump in the Oval Office in January — have largely disappeared from the North’s state-run news media since the Hanoi summit ended abruptly without a deal.

Kim Yong Chol’s negotiating counterpart on the U.S. side had been Secretary of State Mike Pompeo, and their relationship had been frosty.

Pompeo, asked at a news conference in Berlin today about the report that Kim Yong Chol had been purged, said U.S. officials were looking into it.

“We’ve seen the reporting to which you’re referring,” he said. “We’re doing our best to check it out. I don’t have anything else to add to that today.”

Cheong Seong Chang, an analyst at the Sejong Institute, a research organization in South Korea, said it was clear that Kim Yong Chol had lost his position as the top coordinator of North Korea’s negotiations with Washington.

“Kim Yong Chol is the one most to blame for the breakdown of the Hanoi talks,” he said.

But Cheong said he did not think Kim Yong Chol had been banished to a political prison camp, because he retained a party vice chairmanship during a parliamentary meeting in April. Jung Chang Hyun, head of the Korean Peace and Economy Institute, a research group in Seoul, also said that Kim Yong Chol’s presence at a Political Bureau meeting in April indicated that he had survived a purge.

Analysts agreed that Kim Yong Chol’s removal as head of the United Front Department, a major party agency, signaled that his influence had been vastly curtailed at a minimum. Under him, the department had replaced the North’s Foreign Ministry in negotiations with Washington.

“We can say that Kim Yong Chol’s team in the United Front Department has been wiped out,” wrote Joo Sung Ha, a North Korean defector and a reporter at the South Korean newspaper Dong-A Ilbo, who was one of the first journalists to report on Kim Yong Chol’s presumed downfall.

A purge of the department could also mean a prolonged freeze in inter-Korean relations, Joo said, because it historically has shaped the North’s policy on South Korea.

Kim Yong Chol has long been something of an enigma.

During talks between the North and South years ago, he would often cut into a dialogue between the countries’ top delegates. He once asked South Korean officials whether they knew how to kill an elephant with a single rifle shot, indicating that he was comparing the United States to an elephant.

“You shoot the beast right between its eyes,” Kim said, according to former South Korean negotiators.

During his recent negotiations with U.S. officials, however, Kim had lost much of his cockiness, apparently negotiating with strict guidelines from above.

It was all but impossible for U.S. officials to have serious negotiations with him and his team on the specifics on how to denuclearize North Korea, according to officials familiar with the negotiations before the Hanoi summit. Some South Korean officials even wondered privately whether he was mentally as sharp as he used to be.

His stock rose with the first summit between Kim Jong Un and Trump, held in Singapore last June. That meeting produced a vaguely worded promise from Kim to “work toward complete denuclearization of the Korean Peninsula” in return for “new relations” with Washington. It was hailed as a success in North Korea.

Kim Yong Chol’s political undoing came in the second Kim-Trump summit in Hanoi, from which Kim Jong Un returned home without badly needed relief from U.S. sanctions. The outcome was seen as a major humiliation for Kim Jong Un.

Analysts theorized that Kim Yong Chol and other North Korean negotiators mistakenly believed that Trump, eager for something he could tout as a diplomatic achievement, would settle for sanctions relief in return for a partial dismantlement of the North’s nuclear weapons facilities. But Trump demanded a full rollback of the North’s program, and the talks collapsed.

“Someone had to take the blame for the loss of face of the supreme leader, and an obvious scapegoat was Kim Yong Chol and his team,” said Cheon Seong Whun of the Asan Institute for Policy Studies in Seoul.

His downfall could present both opportunities and challenges for Washington, analysts said.

“The North will likely turn more strident with its demands,” Cheon said. “But we must not overestimate the impact of one official in overall North Korea policy. Kim Jong Un is the only one that counts; all others in the North Korean hierarchy are secondary and expendable.”

Cheong of the Sejong Institute said that Kim Yong Chol, a four-star general, had faithfully represented the voice of the North’s hard-line military, which remains deeply wary of relinquishing its nuclear arsenal. His sidelining could open more room for Foreign Ministry officials, who have regained their old role as front-line negotiators with Washington, he said.

“The window for negotiations has become wider — but only if Washington becomes more flexible,” Cheong said. “These Foreign Ministry officials don’t have enough power to completely ignore the voice of the military.”

The rumors of a purge and executions of North Korean negotiators have swirled in official circles in Washington for at least five weeks. Yet, no U.S. official has spoken publicly of any intelligence that would confirm or refute the rumors.

The whispers of a shadowy fate for the North Korean negotiating team has created uncertainty in the Trump administration, as have the recent tests of short-range ballistic missiles by Pyongyang.

But Trump has continued to speak of his confidence in Kim Jong Un in Twitter posts and has encouraged a resumption of diplomacy. He has left open the possibility that he and Kim might have a third summit.

And Pompeo, who has led diplomatic efforts on North Korea for the past year, has sent Stephen E. Biegun, the special representative for North Korea, on trips to Asia to try to restart momentum on negotiations. Biegun was in Singapore today to meet with Asian officials attending the Shangri-La Dialogue, a regional security forum.

Pompeo had been asked at least twice in recent weeks about talk of changes among the ranks of North Korean negotiators. On April 24, Mike Morell, the former acting director of the CIA, told Pompeo during an interview for his podcast, “Intelligence Matters,” that he had heard earlier that morning that Pompeo’s counterpart, presumably Kim Yong Chol, might have “just lost his job.”

Pompeo did not address that, but he did say the Americans were persisting in trying to negotiate with Pyongyang.

“We’re very focused on getting the right set of incentives for both sides so that we can achieve the objective,” Pompeo said. “It’s going to be bumpy. It’s going to be challenging. I hope that we get several more chances to have serious conversations about how we can move this process forward.”

Pompeo said he did see a path to get North Korea to fully renounce its nuclear weapons program, but it solely depended on whether Kim Jong Un makes “the fundamental strategic decision” to denuclearize.

U.S. intelligence chiefs have said they think Kim would never give up his nuclear weapons, an assessment that Trump has ignored.

On May 5, Pompeo was asked on ABC’s “This Week” about rumors that several members of the North Korean negotiating team had been executed.

Pompeo said he had no information to add, then added with a smile, “It does appear that the next time we have serious conversations that my counterpart will be someone else, but we don’t know that for sure.”