Mr Jannuzi, a former deputy executive director of Amnesty International USA, also said he was confident Mr Trump would travel to the Korean peninsula for the talks - as now appears highly likely.
A South Korean government spokesman, Yoon Young-chan, provided remarkable details of a summit meeting the two Korean heads of state held on Friday, when Mr. Kim made history by becoming the first North Korean leader to set foot in the South.
"The Nobel Peace Prize is so well deserved!"
She would know a thing or two about this.
North Korea's leader Kim Jong Un (L on platform) and South Korea's President Moon Jae-in (R on platform) attend at a welcoming ceremony ahead of the inter-Korean summit at the truce village of Panmunjom, South Korea, on April 27, 2018.
Mr Kim is accompanied by nine officials, including his powerful and influential sister Kim Yo-jong.
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President Trump took credit for their peace treaty at his rally in Michigan Saturday night.
The remark was reported by local media and confirmed by South Korea's presidential Blue House. The president's disapproval rating is also at its lowest, 53 percent, in almost 12 months.
Over the weekend, Defense Secretary Jim Mattis, after speaking with his South Korean counterpart, reaffirmed "the ironclad USA commitment" to defend the longtime US ally "using the full spectrum of US capabilities". Meanwhile, a poll from the lesser-known Hangil Research found put Moon's support level at an astounding 86 percent.
Skeptics, however, say that Kim might be duping Moon and Trump into a false peace.
Seoul officials, who have shuttled between Pyongyang and Washington to broker talks between Kim and President Donald Trump that are expected in May or June, said Kim has expressed genuine interest in dealing away his nuclear weapons. "Repeatedly, they have taken actions only to find that those promises proved false or unworthy or they were incapable of keeping them", said Pompeo.
Kim has displayed an about-face since he and Trump traded nuclear threats across the Pacific previous year, now appearing to pursue peace and diplomacy broadly and willingly - though there has been little follow-through on several promises from the North Korean leader. "Just asking!", the president tweeted.
It's an approach that's been shared across East Asia. Some experts say Kim may announce scraping North Korea's long-range missile program, which has posed a direct threat to the United States.