It was a rare peace overture following months of provocations, including a sixth nuclear test and three tests of intercontinental ballistic missiles, that stoked fears of a war on the peninsula.

Still, critics have questioned Kim's sincerity and alleged that the North may be seeking a way out of international pressure and sanctions.

"The end goal and target of this dialogue and meetings between the parties concerned should be the denuclearization -- complete, verifiable and irreversible denuclearization of the Korean Peninsula," Ban said. "And to that purpose, this is a very good beginning, even though it may be a small one."

Ban, a former South Korean foreign minister, expressed support for US President Donald Trump's use of strong language against the North. Trump has threatened to "totally destroy" the isolated nation if necessary and boasted of having a "nuclear button" that is "much bigger and more powerful" than that of Kim.

"There is a tendency to see President Trump's remarks as very provocative rhetoric," Ban said. "But I'd like to interpret it in another way -- it is a strong word and message of international community given to North Korea."

As the "worst norm-breaker" of the international community, North Korea has defiantly challenged all UN Security Council resolutions banning its nuclear and ballistic missile activities, he noted.

"It is important that whether it is termed rhetoric or not, we must be united in sending out a united and very strong message to North Korea, so that they should realize that there is no other way for them to return to the international community as a responsible member (than by) abiding by all these basic norms and principles of United Nations Charter," he said. (Yonhap)