The emotional reaction came hours after US President Donald Trump and North Korean leader Kim Jong-un held their first-ever meeting in Singapore.

In the meeting, Kim reaffirmed his commitment to complete denuclearization of the Korean Peninsula, while Trump agreed to improve the countries' bilateral relationship, according to a joint statement released shortly after their summit.

The South Korean leader said he could expect a successful outcome of the U.S.-North Korea summit after his two recent encounters with Kim at summits on April 27 and May 26 and his latest telephone conversation with his U.S. counterpart, held just the day before the Trump-Kim meeting.

However, 70 years of confrontation between the countries had cast a dark shadow over his eyes to make him doubt what was actually taking place, he said.

"I pay my high compliments for the courage and determination of the two leaders, President Trump and Chairman Kim, not to settle for that outdated and familiar reality but to take a daring step towards change," he said. "The June 12 Sentosa Agreement will be recorded as a historic event that has helped break down the last remaining Cold War legacy on earth."

Moon said the agreement marked a great victory for all people who long for peace.

"Building upon the agreement reached today, we will take a new path going forward. Leaving dark days of war and conflict behind, we will write a new chapter of peace and cooperation. We will be there together with North Korea along the way," he said.

Still, it will be a long journey, he insisted.

"This is just a beginning, and there may be many difficulties ahead, but we will never go back to the past again and never give up on this bold journey," Moon said.

"History is a record of people who take action and rise to a challenge." (Yonhap)