President Trump added that he and Mr Pompeo are "always on the same wavelength". But it also called him "the boss of gangsters", hinting at a different view.
South Korean President Moon Jae-in is set to hold a summit with the North's Kim by the end of April.
"This is a prestige bid by Kim - Kim is inviting Trump to demonstrate that Kim's investment in nuclear weapons and missile capability has brought the U.S.to a position of treating Kim Jong Un as an equal", she said in an email.
FILE - North Korean leader Kim Jong Un shakes hands with Chung Eui-yong, who led a special delegation of South Korea's president, in this photo released by North Korea's Korean Central News Agency, March 6, 2018.
Trump has agreed to meet Kim by May.
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Japan has been more guarded about the prospect of talks between the two Koreas, and between North Korea and the United States. If talks with the U.S. remove some of the most severe sanctions, the pipeline project is likely to be resurrected.
The year leading up to those statements was characterised by as many North Korean missile launches as insults between the two leaders - plus a huge nuclear test on September 3. The North, of course, broke that promise, as it has all undertakings about its weapons programme. And if it does take place, it could be a major coup for Kim, providing the regime with a semblance of global legitimacy.
American commitments under a landmark nuclear deal with Iran offer several lessons for US President Donald Trump as he prepares to enter talks with North Korea over its own nuclear work.
Deputy Secretary John Sullivan met separately with Foreign Minister Kang Kyung-wha of South Korea, the nation which teed up the Trump-Kim summit, and Foreign Minister Taro Kono of Japan, whose nation is less enthusiastic and more skeptical about the sudden spirit of rapprochement. The bill was approved following the death of Otto Warmbier of Wyoming, Ohio, after he had been held in a North Korean prison.
Officials told United States media that chances were low as the Central Intelligence Agency chief has yet to win Senate confirmation.
"I'm very supportive of (Trump's) decision to engage at the highest levels", Yun said.
All the same, there are endless pitfalls.
While the CIA has established a special Korean Mission Center over the past year, the administration has still not appointed a US ambassador to South Korea, a position some analysts say should be central to managing clarity around Washington's posture toward any potential negotiations with Pyongyang.
The administration is renegotiating a free-trade agreement with South Korea.
Adding to the uncertainty is the lack of experienced North Korea hands in Trump's circle. He also asked Seoul to raise the issue of Japanese nationals abducted by the North. Without fully transparent inspections, however, America and its allies will never be sure Kim is living up to his side of the bargain, while South Korea will likely look to China for its ultimate security guarantee.
Korea-hands worry that it is de-escalation that Kim Jong Un is selling, not denuclearisation. One possible ploy might be to forswear missiles that can hit American cities but to preserve a small nuclear arsenal, perhaps under worldwide supervision. That was a crucial point conveyed to Trump by South Korean envoys who recently met with Kim.