Mr Pompeo's returned from Pyongyang on Thursday with three American detainees who had been released by North Korea.
Pompeo also said his talks with Kim on Wednesday were "warm", "constructive", and "good" - and that he made clear that if North Korea gets rid of its nuclear weapons in a permanent and verifiable way, the U.S.is willing to help the impoverished nation boost its economy and living stands to levels like those in prosperous South Korea.
And Pompeo said the United States would remain on board to help develop the North's economy, which has been devastated by its own mismanagement and crippling worldwide sanctions.
In exchange for that USA demand - one that many believe North Korea isn't seriously considering - the U.S.is willing to offer economic assistance, Pompeo said, promising "a future brimming with peace and prosperity".
US Secretary of State Mike Pompeo said Friday that if North Korea agrees to surrender its nuclear arsenal, Washington will work with Pyongyang to rebuild its tiny economy.
"It's a big undertaking for sure, but one that Chairman Kim and I had the opportunity to have a good, sound discussion on, so that I think we had a pretty good understanding between our two countries what the shared objectives are", Pompeo said.
The secretary of State's trip was also used to lay the groundwork for President TrumpDonald John TrumpPruitt dined with Cardinal accused of sexual abuse: report Kelly: No consideration on leaving White House despite "times of great frustration" Kelly: Trump "embarrassed" by Russian Federation probe MORE's expected meeting with Kim, which is scheduled for next month in Singapore. "Conversations that involved deep complex problems, challenges; the strategic decision that Chairman Kim has before him about how it is he wishes to proceed and if he is prepared, in exchange for the assurances we are ready to provide to him, if he is prepared to fully denuclearize".
"The next few weeks will be critical, requiring air-tight coordination between our two countries", Ms Kang said, noting South Korean President Moon Jae-in would be in Washington to see Mr Trump later this month.
He said he had tried to persuade Kim to denuclearize by explaining that historically the United States had often become close partners with its former adversaries.
To the U.S., that means the North giving up the nuclear weapons it has already built. "I really think he wants to do something and bring that country into the real world", he said of Kim.
"This administration has been significantly and sufficiently tough on North Korea".