SEOUL, June 28 (UPI) -- President Trump arrived in Seoul on Saturday evening ahead of a potential meeting with North Korean leader Kim Jong Un in the DMZ.
Trump will have a meeting with South Korean President Moon Jae-in on Sunday and head to the Demiiltarized Zone on the border between South and North Korea, where he may briefly encounter Kim Jong Un.
Trump, who said he "just thought of it this morning," would be the first U.S. president to cross into North Korea.
The president's motorcade was greeted by a large, mostly pro-Trump crowds as it made its way through downtown Seoul en route to a dinner with Moon Jae-in.
Crowds lining a main boulevard waved American and South Korean flags and held up pictures of President Trump. Groups broke out into chants of "Thank you, Trump!" and "USA! ROK!" as the motorcade approached. (The Republic of Korea is the official name of South Korea.)
"We sincerely and strongly welcome Donald J. Trump to Seoul," said Ihn Ji-yeon, spokeswoman for the right-wing Our Republican Party, which helped organize a rally for Trump. "We trust him to support South Korea."
However, she urged caution over nuclear negotiations with Kim Jong Un.
"Kim will never, never, never give up his nuclear weapons," she said.
At a smaller anti-Trump rally earlier in the day, protestors held up reading "No Trump" and "Stop sanctions against North Korea."
Anticipation of meeting had been growing all day since Trump tweeted out an offer on Saturday morning to shake hands and "say hello" to the North Korean leader at the DMZ.
"After some very important meetings, including my meeting with President Xi of China, I will be leaving Japan for South Korea (with President Moon)," Trump tweeted from Osaka.
"While there, if Chairman Kim of North Korea sees this, I would meet him at the Border/DMZ just to shake his hand and say Hello(?)!"
Trump followed up on his tweet in comments to reporters throughout the day.
"I just put out a feeler because I don't know where he is right now, he may not be in North Korea," Trump said in the afternoon, adding that he and Kim "seem to get along very well."
At a wide-ranging hour news conference before departing for Seoul, Trump discussed the potential meeting, saying that his invitation was received "very favorably" by the North Koreans.
He claimed that Kim "follows my Twitter," saying that "we got a very quick call" after tweeting the offer.
North Korea responded with a public statement, calling the proposal "a very interesting suggestion."
"We see it as a very interesting suggestion, but we have not received an official proposal in this regard," North Korean First Vice Foreign Minister Choe Son Hui said in a statement carried by the state-run Korean Central News Agency.
He said a meeting "would serve as another meaningful occasion in further deepening the personal relations between the two leaders and advancing the bilateral relations."
Trump said that he would be willing to step across the border into North Korea if he met with Kim at the DMZ.
"I would feel very comfortable doing that," Trump said. "I would have no problem."
Trump, who has been calling to build a wall on the U.S. border with Mexico since his days on the campaign trail, also expressed admiration for the security of the heavily fortified DMZ in comments earlier in the day.
"By the way, you talk about a wall, when you talk about a border, that's what they call a border," he said. "Nobody goes through that border ... that's called a real border. We're going there, we'll look at it."
If the two leaders do meet, it would mark a dramatic turnaround for a peace process that had been stalled for months.
The last summit between Trump and Kim, held in Hanoi in February, failed to produce an agreement over the North's nuclear program and since then there had appeared to be little movement in negotiations.
Speculation had been growing recently that another meeting may be in the works, however, with Trump and Kim exchanging personal letters.
Stephen Biegun, the U.S. special representative for North Korea, arrived in South Korea ahead of Trump's visit and met with his counterpart, Lee Do-hoon, in Seoul on Friday.
Biegun said that the United States was willing to hold "constructive" talks with North Korea and that it was ready to pursue the commitments made at the first Trump-Kim summit in Singapore "in a simultaneous and parallel manner," according to the South Korean Foreign Ministry.
That summit, held in June last year, produced an agreement in which North Korea pledged to work toward complete denuclearization of the Korean Peninsula, while the two leaders agreed to improve relations and build lasting peace.
The two sides have differed over the timing and sequence of implementing the agreement, however, with Pyongyang seeking concessions, such as the lifting of some international sanctions, in exchange for steps it makes towards dismantling its nuclear program.
Washington has held out for complete denuclearization before sanctions would be lifted, but the comments from Biegun could indicate a softening of that stance.