(ATTN: UPDATES with more quotes, details in paras 4, 8-11)
By Lee Chi-dong and Lee Haye-ah
HANOI, Feb. 28 (Yonhap) -- The much-anticipated second summit between U.S. President Donald Trump and North Korean leader Kim Jong-un abruptly ended without an agreement on Thursday as the two sides refused to back down from their demands for sanctions relief and more denuclearization measures.
Still, Trump said his relationship with Kim remains strong and that the negotiating process will continue.
"Basically, they wanted the sanctions lifted in their entirety, but we couldn't do that," Trump said at a press conference. Trump also said it "was not appropriate" to sign any document under Kim's offer of some denuclearization steps in return.
The totally unexpected outcome underlined the difficulty and unpredictability involved in negotiations aimed at getting the North to give up its nuclear program.
Trump said that the issue of dismantling the North's Yongbyon nuclear complex was discussed in the two-day summit, their first in eight months, but it was "not enough."
"We had to have more than that," he said, adding his administration has information on other, secret uranium-enrichment facilities, which have not been reported by media.
"I think they were surprised we knew," Trump said.
Trump said he wants to take off sanctions, but the North should "give up more."
"He wants to denuke, but he wants to just do areas that are less important than the areas that we want," Trump said. "We know the country very well, believe it or not. We know every inch of that country, and we have to get what we have to get. Because that's a big give."
Asked if he agreed with Kim on a third summit, Trump said, "No we haven't ... we'll see if it happens."
He argued, however, that the Hanoi talks were not without progress, citing Kim's promise to continue the suspension of nuclear and missile testing.
Trump said his relationship with Kim is still "strong" and the atmosphere was "very good, very friendly" when he walked away from the talks.
"This wasn't a walk away like you get up and walk out. No, this was very friendly. We shook hands," he said. "There's a warmth that we have and I hope that stays."
Standing next to Trump and speaking to reporters, Secretary of State Mike Pompeo also said that not reaching a deal in Hanoi does not necessarily mean the denuclearization process has reached a dead end.
"I am still optimistic," he said and expressed hope that Pyongyang and Washington will resume working-level negotiations "in the days and weeks ahead" to resolve the "very complex problem."
Nonetheless, the failure to yield a Hanoi declaration has cast further doubts over the already-troubled denuclearization and peace-building efforts.
It also demonstrated the high risk of a "top-down" approach to deal with the issue, with an ultimate resolution elusive for decades.
Trump and Kim started their Hanoi summit Wednesday in a seemingly amicable atmosphere.
Before noon Thursday, they even talked positively about the establishment of a U.S. liaison office in Pyongyang, although Trump reiterated that he was "in no hurry" for a nuclear deal.
At the start of an expanded meeting, the North Korean leader told a pool reporter that he was discussing "concrete denuclearization measures" in this week's bargaining.
"If I weren't willing to do that, I wouldn't be here right now," Kim said in response to a question about whether he's ready to denuclearize.
The positive mood made its way for skepticism about a deal with news that the leaders cut short their summit.
They called off a joint working dinner and an agreement signing ceremony.
Trump abruptly moved up his press conference by two hours.
Then, Trump's office released a brief statement.
"No agreement was reached at this time, but their respective teams look forward to meeting in the future," White House press secretary Sarah Sanders said in a statement.
It added, "The two leaders discussed various ways to advance denuclearization and economic-driven concepts."
Trump is expected to face harsher criticism of his diplomacy on Pyongyang from critics in Washington D.C.
South Korea's push for closer inter-Korean economic cooperation is likely to suffer a heavy setback.
Kim will have to rethink his strategy, as the voice of hard-line military officials at home may gain some traction.
Kim has kept silent since the end of the summit, staying at his hotel.
On the future of combined military drills with South Korea, meanwhile, Trump questioned whether they are necessary. He cited the huge costs for related operations, including the dispatch of high-tech "strategic assets" to Korea, saying South Korea should provide more financial contributions.
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