The White House on Friday emphasized that the United States had made "zero concessions" in agreeing to face-to-face talks between President Donald Trump and North Korean leader Kim Jong Un.
"We are also operating from a position of strength" that was not there during previous U.S. administrations, White House Press Secretary Sarah Huckabee Sanders said, asserting that as a result of the Trump administration's "maximum pressure" campaign, "North Korea is in a place of weakness."
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Sanders said, "The president will not have the meeting without seeing concrete steps and concrete actions" by Pyongyang, which — South Korean officials say — pledged during an inter-Korean summit to pause its nuclear weapons and ballistic missile testing.
"The president is getting exactly what he wants," which is the "opportunity for the North Koreans to denuclearize," she said.
The White House is insisting that Trump's surprise acceptance — announced by South Korean officials here Thursday — to meet with Kim by May resulted from months of preparation that involved relevant U.S. government agencies.
A deal, the president tweeted Friday, that is "very much in the making."
After South Korean officials on Thursday delivered a verbal message from the North Korean leader to Trump, the U.S. president on Friday morning phoned Chinese President Xi Jinping to discuss the unprecedented U.S.-North Korea leaders' meeting.
Trump and Xi, according to the White House, "welcomed the prospect of dialogue between the United States and North Korea, and committed to maintain pressure and sanctions until North Korea takes tangible steps toward complete, verifiable and irreversible denuclearization. President Trump expressed his hope that North Korean leader Kim Jong Un might choose a brighter path for North Korea's future."
According to the China's state-run Xinhua News Agency, "Xi told Trump that he appreciates the U.S. president's desire to resolve the Korean Peninsula issue politically."
The report adds Xi hopes the U.S. and North Korea will start talks "as soon as possible and strive for positive results," and that "all parties concerned will show goodwill and avoid anything which might affect or interfere with the improving situation on the peninsula."
Japanese Prime Minister Shinzo Abe, who has been suspicious of North Korea's motives, spoke with Trump on Thursday and praised Trump's hardline leadership for forcing Pyongyang to change. Abe said he plans to visit Trump in Washington next month to discuss the summit with North Korea.
Sanders on Friday was asked repeatedly by reporters where and when the meeting between Trump and Kim would occur. She answered that the details are under discussion and no decisions have been made.
U.S. Senator Lindsey Graham, who is a member of the Armed Services Committee, suggested the talks would demonstrate that stepped-up U.S. sanctions are having an impact and warned Kim not to "try to play" Trump in any meeting because "if you do that, it will be the end of you — and your regime."
Graham, a Republican from the state of South Carolina, added, "I do believe that North Korea now believes President Trump will use military force if he has to."
Congressman Eliot Engel of New York, the ranking Democrat on House Foreign Affairs Committee, said, "It's a high-risk gamble, but I would like to see nothing more than a positive outcome from a face-to-face meeting.
"Still, the president should be clear-eyed about Pyongyang's intentions and avoid snap decisions that appear out of step with his top diplomats," Engel said.
It is not clear what Kim will want in exchange for abandoning a nuclear weapons program that has been a core focus since he became supreme leader in late 2011.
The talks are a high-stakes gamble. Success could mean significantly de-escalating tensions over North Korea's accelerated nuclear and ballistic missile tests over the past two years, which have grown sophisticated enough to threaten the U.S. If the talks fail, it could worsen the situation.
Robert Gallucci, chief U.S. negotiator during the 1994 North Korean nuclear crisis, said North Korea's invitation is a "surprising and welcome development." He added, "If representatives of both governments can meet, and a summit ultimately is held, it would represent substantial progress in reducing tension and the risk of war."
"What is new isn't the proposal, it's the response," said Daniel Russel, former U.S. assistant secretary of state for East Asia and the Pacific. North Korea "has for many years proposed that the president of the United States personally engage with North Korea's leaders as an equal — one nuclear power to another," he said.
Trump has been critical of past efforts by the administrations of Bill Clinton, George W. Bush and Barack Obama to resolve the North Korean nuclear threat through negotiations. These past deals slowed the North's nuclear progress, but Pyongyang covertly continued its development efforts and eventually reneged on pledges to dismantle its nuclear facilities.
VOA Correspondent Brian Padden and reporter Lee Yoon-jee in Seoul contributed to this report.