Bill Richardson, a former governor of New Mexico, and Google Executive Chairman Eric Schmidt have ended a private visit to North Korea.
"We strongly urged the North Koreans to proceed with a moratorium on ballistic missiles and a possible nuclear test, that it was important for this step to calm tensions in the peninsula," Richardson told journalists in Beijing shortly after returning from Pyongyang.
However, Richardson, also a former U.S. ambassador to the United Nations, said the trip had failed to secure the release of Kenneth Bae, a Korean-American held captive by North Korea.
He added that he had been unable to meet Bae, a tour operator who was arrested in November in the northern city of Rajin.
"We expressed concern to the North Korean officials" about Bae, Richardson said. "We were informed that his health is good, that the judicial proceedings would start soon. That is encouraging."
He added that "I was also given permission to proceed with a letter from his son, and that will happen shortly."
Richardson said he and Schmidt had urged the authorities to open the country more to modern information technology and communications.
"We strongly urged the North Korean government to increase their use of the Internet -- the Internet is important for the welfare of the North Korean people -- to expand mobile technology, to expand cell phone use," Richardson said.
"I must say that that part of the visit by Dr. Schmidt and his technology advocates and members of his team was the main success of the visit -- more technology exchange, which was well-received by the North Koreans."
Schmidt in turn said Pyongyang should allow its citizens to use the Internet and connect with the outside world, or risk remaining way behind other countries.
The trip was opposed by the U.S. administration, which called it "unhelpful" at a time of heightened tensions with North Korea.
Based on reporting by Reuters and AP