More than three months after Secretary of State Michael Pompeo picked Stephen Biegun to lead negotiations with North Korea, the former Ford Motor Co. executive has barely met officials from Pyongyang face-to-face.

The standstill is a sign of how negotiations between the U.S. and North Korea have faltered, forcing a lowering of expectations, since President Donald Trump met with Kim Jong Un in Singapore in June. Biegun was appointed in August to help follow up on the opening created by the summit, but North Korean officials have ignored Pompeo’s invitation in September to meet with Biegun “at the earliest opportunity.”

Kim’s regime may feel emboldened to spurn the usual channels of diplomacy because Trump has emphasized his personal rapport with the autocratic leader and his interest in holding a second summit soon, according to current and former administration officials.

“The North Koreans are digging in — they just want to deal with Trump,” said Sue Mi Terry, a former CIA analyst who’s now at the Center for International and Strategic Studies in Washington. “Are we closer to some sort of agreement? I don’t think so — people that I talk to say that we’re just genuinely stuck.”

Publicly, Pompeo has remained optimistic and positive about the pace toward eventual success in North Korea. Progress “has been good” and substantive talks continue, he told CNN during the Group of 20 summit in Argentina earlier this month.

Privately, however, the secretary is more downbeat. Two people familiar with his thinking, who asked not to be identified discussing internal deliberations, said Pompeo is growing exasperated that there’s been no progress on the points spelled out at the Singapore summit.

That’s forced the secretary to scale back his expectations for when the North Korea issue could be resolved, the people said. In June, Pompeo said the bulk of denuclearization could be completed by the end of Trump’s first term. Now he — and the president — say they won’t be forced into “artificial time frames.”

“We always knew this would be a long road,” State Department Deputy Spokesman Robert Palladino said in a statement. “Secretary Pompeo entered into negotiations knowing that this would not happen overnight, but no one should question our commitment to fulfilling the Singapore agreement.”

The State Department declined to make Biegun available for an interview.

While there are few public signs of progress — amid reports that North Korea continues to strengthen and expand its nuclear capabilities while stopping short of missile launches and bomb tests — some analysts say there may be more going on behind the scenes. They point to recent South Korean media reports that Andy Kim, the Central Intelligence Agency’s top Korea officer, met last week with North Korean officials in the demilitarized zone between the two Koreas.

A CIA spokeswoman declined to comment on Kim’s travel or confirm whether he met with North Korean officials. Kim, who has announced plans to retire, was a key interlocutor with North Korean officials when Pompeo visited the country as CIA director and, later, as secretary of state.

“The Western media is completely missing the story of U.S.-North Korea contacts other than those at a level of Ambassador Biegun or above,” said Joel Wit, a senior fellow at the Stimson Center in Washington who was involved in North Korea talks from 1993 to 1995. “There evidently have been some working-level contacts that undoubtedly are focused on substantive issues.”

Palladino seconded that view, saying U.S. officials speak “regularly” with North Korean counterparts, adding “we don’t publicize every engagement.”

Pompeo met South Korea’s Foreign Minister Kang Kyung-wha on Thursday. The State Department said they reaffirmed their “ironclad alliance” and pledged to maintain coordination but provided few details on what they discussed. South Korea has moved to ease some tensions with its northern neighbor, sending a train across the border and demolishing some military outposts in conjunction with Pyongyang, even as the U.S. calls for a united front on international sanctions.

Yet within the Trump administration, there are growing strains over how much patience to show with North Korea’s go-slow approach on joint talks. The snubs are hard to ignore: On an October trip to Pyongyang, Biegun’s likely counterpart, Vice Minister for Foreign Affairs Choe Son Hui, was out of the country meeting officials in Russia and China.

U.S. national security adviser John Bolton signaled growing impatience at a Wall Street Journal conference last week.

“They have not lived up to the commitments so far,” Bolton said of North Korea. In a second summit, he said Trump and Kim are “going to discuss this and look at the commitments that were made in Singapore and have a discussion about how they’re going to accomplish those commitments.’

The suggestion that a lack of progress was as good a reason as any to hold another summit frustrated North Korea analysts, who said it only makes Biegun’s job harder.

“It totally cuts Secretary of State Pompeo and the special representative, Steve Biegun, at the knees,” Jung Pak, a senior fellow at the Brookings Institution, said at a Korea Society event in New York on Thursday. “What is the incentive for North Korea to actually talk about the meat-and-potatoes of denuclearization with the special representative and with the secretary of state if the national security adviser has said nothing is happening so we have to go straight to the top?”