ABC News(SENTOSA ISLAND, Singapore) — President Donald Trump lavished praise on North Korean leader Kim Jong Un after their historic four and a half hour face-to-face meeting in Singapore Tuesday, where the two signed an unspecified agreement that the president described as “pretty comprehensive.”

“A very worthy, smart negotiator, absolutely,” Trump told reporters while standing alongside Kim. “We learned a lot about each other and our countries.”

The president made the remarks following a joint signing event with Kim. No details were provided by either delegation of what was contained in the agreements.

“Today we had a historic meeting and decided to leave the past behind and we are about to sign a historic document,” Kim said. “The world will see a major change. I would like to express my gratitude to President Trump to make this meeting happen.”

When asked what surprised him most about Kim, Trump answered, great personality, and very smart. A good combination.

Trump said not only would he “absolutely” be inviting Kim to the White House for a meeting, but he expected the two would meet “many times” in the future.

The friendly banter marked the end of one of the most highly anticipated and high stakes diplomatic meetings in a century.

Both leaders first emerged at 9:03 a.m. local time, walking along a bright red carpet from separate sides of a staging location at the Capella Hotel resort on Sentosa Island to shake hands with a backdrop of U.S. and North Korean flags. The two posed for pictures briefly before walking over to an awning and appeared quite cordial in their greeting, both smiling as they shook hands for a second time.

After taking their seats in a room where they will hold their first meeting of the day, the president briefly engaged in a question from a reporter who asked him how he was feeling.

“I feel really great,” Trump said. “We’re going to have a great discussion, I think, a tremendous success, this will be tremendously successful. It’s my honor and we will have a terrific relationship I have no doubt.”

Kim smiled as he heard the translator interpret the president’s remarks, before weighing in with a brief statement of his own.

“It was not an easy path here,” Kim said. “There’s a history of holding onto our ankles, and it appeared there were times that there were unfortunate practices where they were trying to block our eyes and our ears, but we’ve overcome everything and come to this place.”

As the leaders sat down, White House press secretary Sarah Sanders tweeted photos showing the U.S. and North Korean delegations meeting in a separate room where they watched a video feed showing Kim and Trump together.

Photos showed that National Security Adviser John Bolton was present in the room along with Kim Yong Chol, the high-ranking North Korean military official who hand-delivered a letter from Kim to Trump at the White House on June 1. Bolton has in the past advocated for military action to overthrow the North Korean regime and was more recently a target of searing rhetoric from officials who said in a mid-May statement, “we do not hide our feeling of repugnance towards him.”

Forty-five minutes after going into their one-on-one meeting, Trump and Kim emerged and took a short walk together down a colonnade at the Capella Resort to a separate expanded bilateral meeting.

Trump shouted over a balcony to reporters that the private meeting was “very, very good” and said the two have an “excellent relationship.” Kim did not respond to shouted questions about whether he will give up his country’s nuclear weapons.

The two then sat down with their broader national security delegations for a second meeting. The president was joined by a translator and his chief of staff John Kelly along with Secretary Pompeo and Bolton.

While the president has more recently sought to temper expectations of what he may be able to achieve with the summit, he has also said the interaction amounts to a crucial test in determining whether Kim is genuine in committing to rid his country of its nuclear program.

“I think things could work out very nicely,” Trump said in a Tuesday meeting with Singapore’s Prime Minister Lee Hsien Loong.

The meeting marks the first ever meeting between a sitting North Korean leader and a U.S. president. U.S. officials have said a best case scenario would be that it serves as a launching pad for negotiations that would provide Kim with physical security and his closed off nation with economic assurances in exchange for irreversibly dismantling his country’s nuclear capabilities.

“I believe we’re going to have a terrific success or a modified success,” Trump said during a press conference last week with Japanese Prime Minister Shinzo Abe. “But I really believe that we have the potential to do something incredible for the world. And it’s my honor to be involved.”

The meeting carries not only potentially dire diplomatic risks, but high political stakes as well for a president who has framed the meeting in legacy-defining terms.

While there has been a wave of bipartisan voices looking to support the president’s efforts to avert war in the Korean peninsula, there have also been concerns in foreign policy circles that the meeting will elevate Kim’s status as a brutal dictator overseeing a regime complicit in horrendous human-rights abuses.

The White House has not said whether the president will raise issue with North Korea’s dismal human rights record, but the president took time in the hours before his meeting to take a swipe at critics of the sit-down.

The meeting is also a striking departure for a relationship that just months ago was defined by highly personal insults and rhetoric that seemed to raise the possibility for imminent military confrontation.

In a September 2017 speech in front of the United Nations, President Trump referred to Kim as “Rocket Man” and threatened to “totally destroy North Korea,” which earned a rare rebuke directly from Kim describing the president as a “frightened dog” and “mentally deranged U.S. dotard.”

Following their meetings, Trump will hold a media availability with reporters as Kim Jong Un departs back to North Korea.

Even though President Trump had previously raised the possibility their summit could extend beyond just one day, the White House said Tuesday that the president planned to depart Singapore earlier than originally scheduled as negotiations with the North Korean delegation “have moved more quickly than expected.”

It’s so far unclear whether the U.S. and North Korea will release some kind of joint statement or agreement following the sit-down.

In a briefing with reporters Monday, Secretary of State Mike Pompeo did not set a threshold for whether there’s any terms than North Korea would have to agree to beyond committing to further discussions that would make the summit a success.

“We are hopeful this summit will have set the conditions for future productive talks,” Pompeo said. “In light of how many flimsy agreements the United States has made in previous years, this President will ensure that no potential agreement will fail to adequately address the North Korean threat.”

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