US president Donald Trump has announced he will hold a two-day summit with North Korea leader Kim Jong Un in Vietnam later this month.
Mr Trump has said his outreach to Mr Kim and their first meeting last June in Singapore opened a path to peace. But there is not yet a concrete plan for how denuclearisation could be implemented.
Denuclearising North Korea is something that has eluded the US for more than two decades, since it was first learned that North Korea was close to acquiring the means for nuclear weapons.
“As part of a bold new diplomacy, we continue our historic push for peace on the Korean Peninsula,” Mr Trump said in his State of the Union address.
Director of National Intelligence Dan Coats told Congress last week that US intelligence officials do not believe Mr Kim will eliminate his nuclear weapons or the capacity to build more because he believes they are key to the survival of the regime.
Satellite video taken since the June summit has indicated North Korea is continuing to produce nuclear materials at its weapons factories.
Last year, North Korea released American detainees, suspended nuclear and long-range missile tests and dismantled a nuclear test site and parts of a rocket launch facility without the presence of outside experts.
It has repeatedly demanded that the United States reciprocate with measures such as sanctions relief, but Washington has called for North Korea to take steps such as providing a detailed account of its nuclear and missile facilities that would be inspected and dismantled under a potential deal.
At the second Trump-Kim summit, some experts say North Korea is likely to seek to trade the destruction of its main Yongbyon nuclear complex for a US promise to formally declare the end of the 1950-53 Korean War, open a liaison office in Pyongyang and allow the North to resume some lucrative economic projects with South Korea.
“Our hostages have come home, nuclear testing has stopped, and there has not been a missile launch in 15 months,” Mr Trump said. “If I had not been elected president of the United States, we would right now, in my opinion, be in a major war with North Korea.”
“Much work remains to be done, but my relationship with Kim Jong Un is a good one,” he said in announcing their second meeting on February 27 and 28.
Stephen Biegun, Secretary of State Mike Pompeo’s special representative for North Korea, is hopeful, but acknowledges that many issues make it especially complicated for the two countries to “embark on a diplomatic initiative of this magnitude”.
The Vietnamese city where the two leaders will meet was not announced.