Both Pyongyang and Washington are pressing ahead on plans for a summit after Trump pulled out of the proposed June 12 meeting on Thursday, only to reconsider the decision the next day.
"A U.S. delegation is in ongoing talks with North Korean officials at Panmunjom," spokeswoman Heather Nauert said, referring to a village in the Demilitarized Zone (DMZ) that runs along the heavily armed border between North and South Korea.
"We continue to prepare for a meeting between the President and North Korean leader Kim Jong Un," she said in a statement.
In addition to the border talks, White House spokeswoman Sarah Sanders said a "pre-advance team" left for Singapore on Sunday morning to work on logistics for a possible summit.
Earlier on Sunday, South Korean President Moon Jae-in said he and North Korea's Kim had agreed during a surprise meeting on Saturday that the North Korea-U.S. summit must be held.
A U.S. official told Reuters that Sung Kim, the former U.S. ambassador to South Korea, would lead an American delegation to meet North Korean officials at the border. Pentagon official Randall Schriver was part of the U.S. team, the official said.
The Washington Post first reported that the team, which also included Allison Hooker, the Korea expert on the White House National Security Council, met with Choe Son Hui, the North Korean vice foreign minister.
"Chairman Kim and I have agreed that the June 12 summit should be held successfully, and that our quest for the Korean Peninsula's denuclearization and a perpetual peace regime should not be halted," Moon said.
Moon acknowledged Pyongyang and Washington may have differing expectations of what denuclearization means and he urged both sides to hold working-level talks to resolve their differences.
The United States has demanded the "complete, verifiable, and irreversible" dismantlement of North Korea's nuclear weapons program. Pyongyang has rejected unilateral disarmament and has always couched its language in terms of denuclearization of the Korean Peninsula.
In previous, failed talks, North Korea said it could consider giving up its arsenal if Washington removed its troops from South Korea and withdrew its so-called nuclear umbrella of deterrence from South Korea and Japan.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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