Stephen Bosworth, former US ambassador to South Korea and now dean at the Fletcher School of diplomacy at Tufts University, said following talks with senior North Korean officials he got with the impression they wished to continue with the nuclear disarmament process.
"We concluded that the outlook is that we can continue to work towards eventual denuclearisation of the Korean peninsula," Bosworth told reporters in Beijing.
He said the North Koreans appeared to understand it would take some time for new US President Barack Obama's administration to review policy towards Pyongyang.
"They expressed patience. There's no sense of alarm or urgency," Bosworth said.
He and other US experts visited Pyongyang for five days as a non-government delegation, meeting North Korean officials and returning via the Chinese capital.
The message he conveyed from isolated Pyongyang came while regional powers worry the North may seek to win attention and leverage by test-firing short-range missiles into a disputed maritime border with South Korea or even firing long-range ones.
Bosworth said his group had indicated there was concern about the possibility of a missile test, but the North Korean officials neither confirmed nor denied any plans.
"They said we should all wait and see. There was no threat, no indication that they were concerned. They treated the missile issue as just another run of the mill issue," he added.