North Korean leader Kim Jong Un is willing to hold a second summit meeting with U.S. President Donald Trump soon to move ahead with denuclearization negotiations, South Korean President Moon Jae In said Thursday following his three-day visit to Pyongyang.

Hours after he returned to Seoul, Moon, who had talks with Kim twice during his stay in North Korea, also told reporters that Kim voiced readiness to complete denuclearization in the near future.

The North Korean leader "kept confirming and reconfirming his firm will toward denuclearization. He wishes to achieve complete denuclearization as soon as possible so that he could focus on economic development," Moon said.

He said Kim looked forward to a second dialogue with Trump after the first held in Singapore in June and indicated he would welcome a visit by U.S. Secretary of State Mike Pompeo to Pyongyang.

According to a joint declaration signed by the two leaders after their summit talks, Kim pledged to Moon that North Korea will permanently dismantle its major nuclear complex if the United States takes corresponding actions.


[Pyeongyang Press Corps]

But the September Pyongyang Joint Declaration did not specify how and when North Korea will abandon all its nuclear weapons, even though Washington has called on Pyongyang to show a clear roadmap toward denuclearization.

"Gradual steps that North Korea should take to attain complete denuclearization, corresponding measures that the United States must take and also the steps of them should be discussed between North Korea and the United States," Moon said.

The South Korean president said he is scheduled to hold a meeting with Trump on Monday on the sidelines of the U.N. General Assembly in New York.


[Pyeongyang Press Corps]

At their June 12 summit in Singapore, Trump and Kim agreed that Washington will provide security guarantees to Pyongyang in exchange for "complete" denuclearization.

The Pyongyang summit talks were held amid doubts over whether North Korea really intends to get rid of its nuclear arsenal. The United States has criticized it for not doing enough to fulfill the June 12 agreement.

Moon, who left North Korea for Seoul late afternoon on Thursday, has expressed eagerness to serve as a "broker" between Trump and Kim.

He said North Korea should also give up its intercontinental ballistic and long-range missiles to accomplish complete denuclearization on the Korean Peninsula.

On Thursday, the leaders of North and South Korea visited Mt. Paektu, the highest mountain on the Korean Peninsula and a spiritual symbol for the Korean people.

The 2,744-meter volcano on North Korea's border with China is considered sacred by Koreans as, according to folklore, it was the birthplace of the founder of the first Korean kingdom.


[Pyeongyang Press Corps]

But as North Korea tells it, it is the place from which Kim Il Sung, Kim's grandfather who founded the country in 1948, led an anti-Japanese partisan group, as well as the birthplace of Kim Jong Il, the current leader's father.

At nearby Samjiyon airport, Moon was greeted by Kim, who had flown in from Pyongyang earlier, the South Korean government said.

From the airport, Moon and Kim traveled by car to the top of the mountain and posed for photos at viewing platform that overlooks a huge crater lake.

The post-summit excursion was suggested by Kim as Moon previously indicated he hoped to visit there directly from the North Korean side rather having to do so from the Chinese side, the government said.

After visiting the mountain, Moon returned to Seoul, flying directly to Seongnam Air Base from Samjiyon, concluding his three-day visit to North Korea for his third summit with Kim.

Before Moon's departure, Kim sent the president two tons of pine mushroom, the government said, adding the North Korean delicacy will be shared with members of South Korean families separated from their northern kin by the 1950-1953 Korean War.

At the summit, Kim, meanwhile, promised to visit Seoul "in the near future," possibly by the end of this year, raising the possibility that he will become the first North Korean leader to travel to the South Korean capital.

The two Koreas also agreed to take a set of measures to ease military tensions between them and further improve their ties.

Those include disarming the Joint Security Area in Panmunjeom, a border village in the Demilitarized Zone dividing the two Koreas, halting all drills near the Military Demarcation Line from Nov. 1, and removing some border guard posts within the DMZ.

On Tuesday, Moon became the third South Korean president to visit Pyongyang. Kim Dae Jung went there in 2000 and Roh Moo Hyun in 2007, both for talks with Kim Jong Il.