An ex-United States diplomat returned Friday from a five-day visit to North Korea, where he urged Pyongyang to free Korean-American missionary Kenneth Bae.
Donald Gregg said Friday that Bae's fate was not the main purpose of his trip, but that he raised the issue during meetings with North Korean Foreign Ministry officials.
"I urged that he be released. But that was not on our agenda, and we just felt that we needed to say that," said Gregg.
Gregg was the U.S. ambassador to South Korea from 1989 to 1993. The U.S. State Department said Gregg's visit to Pyongyang was not on behalf of Washington.
Gregg is now chairman of the U.S.-based Pacific Century Institute. He said North Korean leaders are not optimistic about relations with the United States.
"They hope that it will improve, but they're very optimistic about their own ability to grow stronger economically here, and they will just hope that relations between our two countries will improve in the not too distant future," said Gregg.
The fate of Bae has been one of many issues challenging the U.S.-North Korean relationship. The 45-year old is serving a 15-year sentence of hard labor after being found guilty of trying to overthrow the government.
There had been hope that Gregg's trip would help win Bae's release, after North Korea withdrew an invitation for a senior American envoy to discuss the case.
The U.S. believes the North withdrew the invitation for Robert King, the U.S. Special Envoy for Human Rights Issues, because of joint U.S.-South Korean military drills.
Last week, the U.S. State Department said Bae has been transferred from a hospital to a labor camp.
North Korea arrested Bae in late 2012.
Calls for his release on humanitarian grounds have gone unanswered.
Bae was born in South Korea and emigrated to the United States with his parents and sister in 1985. He was living in China as a Christian missionary for about seven years before his arrest.
Within the last few years, he began leading small tour groups, mostly of American and Canadian citizens, into a "special economic zone" designed to encourage commerce in northeastern North Korea.