"Hopefully it can be done as expeditiously as possible, but I think we have to be realistic".
He became the highest level figure from North Korea to hold talks at the White House since a senior envoy visited former US President Bill Clinton in 2000.
"I know Rudy", he told reporters at the White House after a meeting between Mr. Trump and Japan's prime minister.
Still he predicted he'll know very quickly whether Kim is serious about dealing with USA demands.
Before threatening to walk away from talks the first time, North Korea had bemoaned American attempts to "drive us into a corner" and force disarmament. "Sounds a little bit unusual, but that's probably the easy part". "The hard part remains after that". Multiple US and N Korean teams are holding simultaneous meetings ahead of the Singapore Summit. "But it wasn't so I'll solve it and we'll get it done", Trump said.
Trump also said Kim's letter to him "was just very nice", but did not say much "other than we look forward to seeing you". "What he did was he called off the summit", he said.
The United States stations 28,500 troops in South Korea, a legacy of the Korean War.
"I'm not able to talk about the details of what we discussed". Pompeo said Trump will reject anything short of "complete, verifiable and irreversible denuclearisation of the Korean Peninsula".More news: Rescuers tirelessly search for 200 missing near Guatemala volcano
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Mueller is investigating whether Trump associates coordinated with Russian Federation during the 2016 presidential election and whether Trump took steps to shut down that investigation through actions, including the firing of FBI Director James Comey.
"The fact was no USA president wanted to do this, and for good reason", he said.
Pompeo, however, added that the United States would work to guarantee North Korea's security should it denuclearise. Trump also dismissed the notion that the meeting, planned for June 12, would be a mere "photo op" and said it would be "exciting" and "fruitful".
Trump is to huddle with Secretary of State Mike Pompeo and National Security Adviser John Bolton Thursday afternoon "to continue their strategic discussions" ahead of the summit, said National Security Council spokesman Garrett Marquis.
"He has indicated to me personally that he's prepared to denuclearize". "That he understands that the current model doesn't work, that he's prepared to denuclearise and that two, he understands that we can't do it the way we've done it before". "If they don't de-nuclearize, that will not be acceptable".
The potential for on-the-fly negotiations is fueling a White House debate about what - if any - concessions Mr. Trump should offer in exchange for North Korea's concrete steps toward dismantling nuclear weapons and nuclear weapons facilities.
The Japanese leader is seeking to ensure that Trump's efforts to negotiate an agreement with Kim don't harm Japan's interests.
Since the first inkling that a Trump-Kim summit could be on the cards, Japan has repeatedly insisted that Washington be mindful not to let its guard down with the nuclear-armed regime in Pyongyang.