American and North Korean officials met at the border between North and South Korea on Sunday in preparation for a possible North Korea-US summit, as North Korea’s Kim Jong Un was cited as reaffirming his commitment to meet with US President Donald Trump. 

Trump on Sunday said in a tweet that a meeting between him and North Korea's Kim Jong Un will happen, after cancelling the summit just last week.

The US and North Korean officials met at the heavily armed border between North and South Korea in an effort to lay the groundwork for a Trump-Kim face-to-face.

The White House also said a "pre-advance team" left for Singapore on Sunday morning to work on logistics for a possible summit.

Trump pulled out of the proposed June 12 meeting on Thursday, only to reconsider the decision the next day, after the North Korean leader was cited as reaffirming his commitment to meet with him.

Earlier on Sunday, South Korean President Moon Jae-in said the meeting must go forward.

"We (Kim and Moon) have agreed that the June 12 summit meeting should be held successfully, and that our journey for the Korean peninsula's denuclearisation and a perpetual peace system should not be halted. We have agreed to cooperate with each other for this," the South Korean President said.

Moon and Kim held a surprise meeting on Saturday - the strongest sign yet that the leaders of the two Koreas are trying to keep the on-again, off-again meeting between Trump and Kim on track.

Kim also reaffirmed his commitment to "complete" denuclearization of the Korean Peninsula.

After the meeting, Moon acknowledged that Pyongyang and Washington may have differing expectations of what denuclearization means.

American officials are sceptical that Kim will ever fully abandon his nuclear arsenal, and Moon said North Korea is not yet convinced that it can trust security guarantees made by the U.S.