SEOUL, South Korea (TNS) — The hugs, smiles and apparent mutual admiration between the leaders of the estranged Koreas at a summit Friday set the stage for President Donald Trump to move ahead with his own plans for a face-to-face meeting with North Korean leader Kim Jong Un.

The challenge, however, will be to turn the bonhomie seen at the demilitarized zone separating North Korea and South Korea into an actual deal in which the isolated government in Pyongyang takes tangible steps toward denuclearization.

Among those most enthusiastic about the prospects seemed to be Trump, who reacted to the meeting between Kim and South Korean President Moon Jae-in by telling reporters at the White House he was finalizing plans to meet Kim. Two or three locations were under consideration, he said.

"Hopefully, we are going to have great success," said Trump, who was hosting German Chancellor Angela Merkel. "This is going to be a great thing for the world."

Trump, once among Kim's harshest critics, said the North Korean leader seemed sincere about negotiations.

"Oh, I don't think he's playing. You know, it's never gone like this. It has never gotten this far," he said. "The United States in the past has been played like a fiddle ...That's not happening to us. We will, I think, come up with a solution."

Trump repeated a threat that he would walk out of a summit with Kim if they were making no progress.

During Friday's summit at Panmunjom, the so-called peace village straddling the North-South border, Kim and Moon signed a joint statement in which they "solemnly declared before the 80 million Korean people and the whole world that there will be no more war on the Korean peninsula and thus a new era of peace has begun."

They promised to work toward an eventual peace treaty to end the Korean War, which was halted by an armistice in 1953.

They also confirmed a "common goal" of denuclearization, a key point for South Korea's main ally, the United States — though they stopped short of a firm commitment.

The day's events were rich in pomp and symbolism. Moon wore a light blue tie in the color of a flag meant to symbolize Korean unification, while Kim stuck to a Mao suit, affirming his country's commitment to socialism.

In one unplanned moment, Kim invited Moon to step across the border into North Korea just after their historic greeting, and the South Korean president warmly obliged.

"You have crossed over to the South, but when will I be able to cross over to the North?" Moon said, according to Moon's spokesman. Kim responded, "Why don't you cross now?" and held Moon's hand as they stepped over the line.

Among the day's activities, the two leaders donned white gloves and ceremonially poured soil and water onto the base of a pine tree symbolizing peace and prosperity — an event rich in irony given the history of the location. (Among the many skirmishes over the years at the spot, there is the infamous axe murder incident from 1976, in which two U.S. soldiers trying to prune a poplar tree were killed by North Korean troops.)

After the tree ceremony, the pair walked along the east side of the compound, sitting down for a discussion under clear skies and temperate weather, birds chirping in the background. The pair seemed engaged, nodding and smiling as they talked — away from their staffs and nearby cameras.

To longtime North Korea watchers, the summit evoked a sense of deja vu. In 2000, then-South Korean President Kim Dae Jung went to Pyongyang to meet Kim Jong Il, the father of the current leader, a trip for which he won the Nobel peace prize later that year. That summit preceded a giddy period of rapprochement — with joint concert, soccer matches, cross-border tours and economic ventures — before it all fizzled.

"We've seen this show before, not for a while, but it's not so much different from what happened before," said Sue Mi Terry, a former CIA analyst now with the Center for Strategic and International Studies. She said she doubts whether Kim Jong Un is truly willing to give up the nuclear weapons and missiles that have been so far the crowning achievement of his government.

The North Koreans have said they need their nuclear weapons as a deterrent to protect their leadership from being toppled along the lines of Iraq's Saddam Hussein and Libya's Moammar Gadhafi.

"I don't want to rain on the parade, but we don't have a single indication that Kim is really willing to put his nuclear weapons on the table," said Terry. "This could be more of a tactical shift."

"It was a pretty dramatic aspirational moment. It pulled at all the heart strings," the Council on Foreign Relations' Scott Snyder said of Friday's meeting. But Snyder said that practically speaking the hard work is just beginning.

"What Kim has done so far is bring us back to the starting line for talks. The question is whether the talks can lead anywhere or if this is all we get."

Some observers said the latest developments could signal a new era in inter-Korean relations, perhaps ending the decades-long tensions, and an end to the missile and nuclear testing by the North that prompted worldwide condemnation and heightened economic sanctions last year — as well as the bombastic comments Kim and Trump made about each other.

John Delury, an associate professor at Yonsei University in Seoul, saw promise in the exchanges between Kim and Moon.

"I saw a lot of spontaneity — what I would say was an authentic dialogue between these two leaders," Delury said. "There's a serious burden on both of these leaders' shoulders, in a place where many of us thought this was slipping toward a serious military confrontation ... . Kim Jong Un is shattering our expectations that he won't do this stuff. He's doing it."

He said the "restraint" in the agreement showed prudence ahead of Kim's expected meeting with Trump in several weeks.

The agreement signed by the two leaders focused on three main goals: improving strained inter-Korean relations, reducing military tensions and working toward a peninsula free of nuclear weapons — weapons that the North has sought for years in spite of United Nations resolutions barring the effort.

Kim has promised not to conduct further nuclear tests or intercontinental ballistic missile tests while talks are pending and has offered to close down the test site where six underground nuclear tests have been conducted since 2006. But he has not offered to freeze production of nuclear material — or more importantly to dismantle his existing arsenal of up to 60 nuclear warheads.