It's the summit eve in Singapore. Global anticipation of the meeting between U.S. President Donald Trump and North Korea's third-generation autocrat Kim Jong Un is close to feverish. It's the biggest, and most mind-boggling, summit of its kind this century — and probably for several decades.

Imagine if President George W. Bush had met Iraqi leader Saddam Hussein for face-to-face negotiations in January 2003 in Egypt instead of the U.S.-led invasion going ahead two months later and you get a sense of how remarkable this summit is.

As the hours count down to the Tuesday morning meeting, here's a look at what happened in Singapore and the Koreas on Monday.

ELEVENTH HOUR MEETINGS, BRIEFINGS AND AN ABSENCE

— Trump met Singaporean Prime Minister Lee Hsien Loong, as Kim did on Sunday, was feted at lunch with an early birthday celebration (his birthday is June 14), and then went back to his hotel, the swanky Shangri-La. Along the way, he offered "that things can work out very nicely" with North Korea.

— The White House said Trump would be leaving Singapore early because the nuclear negotiations have moved "more quickly than expected." It was not clear whether that was a sign of progress.

— North Korean and American delegations met at the Ritz Carlton., not once, but twice. Last-minute bargaining, leverage hunting and final protocol details perhaps on the agenda before their bosses shake hands and sit down.

— U.S. Secretary of State Mike Pompeo briefed reporters, insisting Washington is prepared to take actions to provide North Korea with "sufficient certainty" that denuclearization "is not something that ends badly for them."

— South Korean President Moon Jae-in has no current plans to join Trump and Kim at the end of their summit. Moon had expressed hope that the meeting will lead to a three-way declaration also including South Korea on formally ending the 1950-53 Korean War. But Moon has to be present when and if such a document is signed.

WHERE WAS KIM YESTERDAY?

— After staying out of public view at the St. Regis hotel for most of the day, Kim ventured out in the evening for a city tour that included the well-known tourist spot Gardens by the Bay. Singaporean Foreign Minister Vivian Balakrishnan posted a selfie of him and a smiling Kim wearing his trademark dark Mao suit. Flanked by bodyguards, Kim also visited the Marina Bay Sands resort. North Koreans were told by state media for the first time Monday that Kim is meeting Trump. One man exclaimed, "I know that Singapore is a very hot country so I wish that our respected marshal stays healthy and comes back in good health."

THE FACE-TO-FACE

— Trump and Kim will start their historic summit at Sentosa Island with a one-on-one session with translators. After that no one really knows how it will play out. Anything is possible, from a grandiose declaration that the Korean War will be formally ended in the near future, with the far more complex lynchpin of denuclearization on the back burner, to a rapid collapse of talks with someone abruptly walking away.

AP