(CNN) US Vice President Mike Pence's trip to South Korea for the PyeongChang Winter Olympics has been called "a missed opportunity" by a senior diplomatic source close to North Korea.
When asked about Pence's remarks to the Washington Post of a possible diplomatic opening between the two countries, the source said North Korea remains skeptical given that he appears to have spoken on his own, without co-ordination from the White House and State Department.
In the interview, Pence said the US and South Korea agreed on terms for further engagement with North Korea, calling the diplomatic path "maximum pressure and engagement at the same time."
"The point is, no pressure comes off until they are actually doing something that the alliance believes represents a meaningful step toward denuclearization," Pence is quoted as saying. "So the maximum pressure campaign is going to continue and intensify. But if you want to talk, we'll talk."
The senior diplomatic source said Pence "degraded the image of the United States as a superpower" by meeting with North Korean defectors along with Otto Warmbier's father, and by speaking strongly against North Korea on multiple occasions.
Fred Warmbier accompanied Pence during his visit to South Korea. His son Otto was jailed in North Korea and died upon his return to the US last year after suffering extensive brain damage.
Throughout his visit, observers said Pence seemed uncomfortable with the warm welcome the North Korean delegation received from the South.
Over the weekend, Kim Yo Jong, the younger sister of leader Kim Jong Un visited Seoul and met with President Moon Jae-in, a historic first by any member of the ruling Kim family and the most significant diplomatic development in the Kim Jong Un era.
Along with Kim Yong Nam, the ceremonial head of state, and other North Korean officials, the pair attended Olympic events and visited the Blue House, the presidential palace in Seoul.
There, Kim Yo Jong signed the guest book, expressing hope that "Pyongyang and Seoul get closer in our people's hearts and move forward the future of prosperous unification." She also extended an invitation to President Moon to visit her brother in Pyongyang, which potentially sets up the first meeting of Korean leaders since 2007.
The source also described as "undignified behavior" Pence's decision to stay seated and to not applaud the unified Korean team at the opening ceremony, adding that the Vice President "took the low road instead of acting like a big brother."
During the ceremony, Pence sat just feet away from Kim Yo Jong and looked stony faced as President Moon twice shook hands with her.
Even a small gesture of respect, the source said, could have led to a diplomatic opening between North Korea and the US that would have helped to increase trust between the two countries. Instead, Pence was criticized by North Korean media, accused of not respecting the "Olympic spirit."
The source added, however, that North Korea could still be willing to work with the United States on a "comprehensive and integrated agreement," under the right conditions — adding "denuclearization could mean many things," including an agreement to suspend missile and nuclear tests in exchange for limited recognition or acceptance of its nuclear status.
The United States' position on dialogue with North Korea hasn't exactly been consistent.
US Secretary of State Rex Tillerson said in December the US was ready to talk without preconditions, only to have the White House nix the notion.
Officials in the Trump administration have previously said a North Korean commitment to denuclearization up front was necessary to kick start talks.
In September, Tillerson said the situation on the Korean Peninsula was "overheated" and would need to calm down before any conversations were to take place.