Watch: George W. Bush says U.S. can't afford to 'drift' on North Korea

DALLAS, Nov. 29 (UPI) -- Former President George W. Bush said Tuesday that North Korea continues to pose a grave security threat to the United States and compared the country to a "prison run by a sadistic warden."

Bush made the remarks during a forum on North Korean human rights held at the Bush Institute in Dallas, where top experts and U.S. government officials convened to provide recommendations on next steps for North Korea.

While the theme of the gathering was human rights and the experiences of North Korean defectors, participants took the moment to define what U.S. North Korean policy ought to look like in a time of transition.

"This is a timely moment," Bush said in his opening remarks, while not mentioning President-elect Donald Trump by name. "After all, our country is about to have a new administration, which of course has every right to choose its own direction. They can take advice or not. But there's one option that can't be chosen: the option of drifting, because that current would lead to disaster."

Trump and his transition team have had little to say about North Korea since the Nov. 8 election, and Pyongyang's nuclear weapons proliferation and other security issues related to U.S. allies in Asia were not included in his 100-day plan.

But the president-elect pledged "100 percent" support for the U.S.-South Korea alliance in tackling North Korea's nuclear provocations during a phone call with South Korean President Park Geun-hye.

Experts appeared to be filling in the missing gaps on Tuesday, including two veteran U.S. negotiators and government officials, Victor Cha and Robert Gallucci, who have published suggestions for what Bush described as a "renewed North Korean policy."

Cha and Gallucci's "roadmap," Bush said, "reassures important allies in the region, integrating nonproliferation and human rights sanctions, going after slave labor exports that fund weapons development, encouraging information flows into the North and expanding diplomatic pressure."

Other participants, including Sen. Cory Gardner, R-Colo., and former Connecticut Sen. Joseph Lieberman, agreed the next administration would have to face North Korea and make it a priority.

The forum also featured North Korean refugees Grace Jo and Joseph Kim, who have resettled in the United States since they escaped what Jo described as a "very cruel system."

Both refugees have said they lost family members in North Korea.