Trump has returned to his hotel after meeting with Singapore's Prime Minister Lee.
After months of nuclear taunts, sports diplomacy and a rollercoaster of a will-they-or-won't-they tango, it all comes down to this: President TrumpDonald John TrumpTrump: "Excitement in the air" ahead of Kim meeting Trump doubles down on criticism of EU, Canada Merkel: EU will retaliate against Trump tariffs MORE will meet face-to-face with North Korean leader Kim Jong Un in Singapore on Tuesday.
Kim arrived in Singapore mid-afternoon Sunday, amid much speculation about the outcome of Tuesday's talks.
Trump canceled the meeting, but made a decision to move ahead with it a week later after a visit to Washington by a top North Korean official.
Authorities have beefed up security around the hotels where Trump and Kim (Saint Regis) will be staying in central Singapore. The North Korea side is being led by Vice Foreign Minister Choe Son-hui. USA officials were quoted as saying that the two leaders could spend the first two hours alone with translators but not advisors.
It continues: "Even if a country had a hostile relationship with us in the past, our attitude is that if this nation respects our autonomy. we shall seek normalisation through dialogue".
Why only potentially? That's because these two world leaders are not, strictly speaking, known to be very diplomatic - that is to say that they are in no manner of speaking, known to be very diplomatic at all.
But there are doubts denuclearisation of North Korea is achievable in the short term. "I feel that Kim Jong Un wants to do something great for his people and he has that opportunity".
Experts believe the North is on the brink of being able to target the entire U.S. mainland with its nuclear-armed missiles, and while there's deep skepticism that Kim will quickly give up those hard-won nukes, there's also some hope that diplomacy can replace the animosity between the United States and the North.
Ahead of the meeting, Trump has dangled the carrot of a normalisation of diplomatic ties between the former foes and even a White House visit for Kim, which would confirm his arrival on the world stage.
Kim may also be seeing the gamble in a light never considered by his autocratic father and grandfather because of "his determination to modernize North Korea", according to Ryan Haas, an Asia expert at the John L. Thornton China Center.
And until denuclearisation takes place, sanctions against North Korea would remain in place, he stressed.
Asked by a reporter how he felt about the summit, Trump said: "Very good". He told Lee: "We've got very interesting meeting in particular tomorrow, and I just think it's going to work out very nicely".
The top USA and North Korean negotiators had earlier emerged from a last-ditch meeting at the Ritz Carlton with pursed lips, and no sign of whether an attempt to narrow the gap between USA and North Korean expectations of what denuclearisation should look like, had worked.
Mr Trump's first year in office was marked by bitter exchanges between himself and Mr Kim - as North Korea conducted several ballistic missile tests in defiance of the worldwide community.
Mr Kim has also said he wants to focus on building the North Korean economy - and thus wants sanctions relief and worldwide investment.