US officials have met North Korean counterparts at the border village of Panmunjom as talks continue over a potential summit between President Donald Trump and North Korean leader Kim Jong Un.

State Department spokeswoman Heather Nauert said a “US delegation is in ongoing talks with North Korean officials” inside the Demilitarized Zone between North and South Korea that was created at the end of the Korean War.

She said preparations are moving ahead for a meeting between the two leaders.

Mr Trump said on Saturday that conversations about a potential summit were “going along very well”.

He announced on Thursday that he was withdrawing from the scheduled June 12 meeting in Singapore, only to say on Friday that the summit might be back on.

Earlier, South Korean president Moon Jae-in said that the North Korean leader had committed during a surprise meeting to sitting down with Mr Trump and to a “complete denuclearisation of the Korean Peninsula”.

North Korea Koreas Tensions
South Korean president Moon Jae-in writes in a visitor’s book as North Korean leader Kim Jong Un, looks on (AP)

The Korean leaders’ second summit in a month saw bear hugs and broad smiles, but their quickly arranged meeting appears to highlight a sense of urgency on both sides of the world’s most heavily armed border.

The Koreas’ talks, which Mr Moon said Mr Kim requested, capped a whirlwind 24 hours of diplomatic back-and-forth.

It allowed Mr Moon to push for a US-North Korean summit that he sees as the best way to ease animosity that had some fearing a war last year.

Mr Kim may see the sit-down with Mr Trump as necessary to easing pressure from crushing sanctions and to winning security assurances in a region surrounded by enemies.

Mr Moon told reporters on Sunday that Mr Kim “again made clear his commitment to a complete denuclearisation of the Korean Peninsula,” and told the South Korean leader that he is willing to cooperate to end confrontation and work toward peace for the sake of the successful North Korea-US summit.

Mr Moon said he told Mr Kim that Mr Trump has a “firm resolve” to end hostile relations with North Korea and initiate economic cooperation if Kim implements “complete denuclearisation”.

“What Kim is unclear about is that he has concerns about whether his country can surely trust the United States over its promise to end hostile relations (with North Korea) and provide a security guarantee if they do denuclearisation,” Mr Moon said.

“During the South Korea-US summit, President Trump said the US is willing to clearly put an end to hostile relations (between the US and North Korea) and help (the North) achieve economic prosperity if North Korea conducts denuclearisation.”

Mr Moon said North Korea and the United States will soon start working-level talks to prepare for the Kim-Trump summit. He said he expects the talks to go smoothly because Pyongyang and Washington both know what they want from each other.

Mr Kim, in a telling line from a dispatch issued by the North’s state-run news service earlier on Sunday, “expressed his fixed will on the historic (North Korea)-US summit talks.”

During Saturday’s inter-Korean summit, the Korean leaders agreed to “positively cooperate with each other as ever to improve (North Korea)-US relations and establish (a) mechanism for permanent and durable peace.”

They agreed to have their top officials meet again on June 1.

Mr Moon said military generals and Red Cross officials from the Koreas will also meet separately to discuss how to ease military tensions and resume reunions of families separated by the 1950-53 Korean War.