In a farewell letter to outgoing South Korean President Moon Jae-in, the North Korean leader praised his efforts to bring the two countries closer together.
In the letter, Kim Jong-un "appreciated the pain and effort Moon Jae-in endured for the great cause of the nation up to the last days of his tenure," the official KCNA news agency reported on Friday.
Friederike Böge
Political correspondent for China, North Korea and Mongolia.
Follow I follow
The ruler recalled the "historic joint declaration" in which the two heads of state committed themselves at their first summit in April 2018 to taking steps towards denuclearization of the Korean peninsula.
The meeting paved the way for inter-Korean rapprochement and three meetings between Kim and then-US President Donald Trump.
Successor for a harder pace
However, there have been no further negotiations since the Hanoi Summit in February 2019.
North Korea repeatedly frustrated Moon's efforts to get closer and blew up the liaison office in the border town of Kaesong.
With his letter, Kim reacted to a farewell letter from Moon, in which he called on the North Korean to enter into dialogue with his successor Yoon Suk-yeol and to resume negotiations with America.
Observers also see Kim's statements as a message to Yoon, who takes office on May 10.
The conservative politician has announced a tougher approach to dealing with North Korea.
Among other things, he claimed the right for his country to forestall a North Korean missile attack with a pre-emptive strike.
Amidst Kim's praise of his predecessor is a warning that if the relationship deteriorates further, the new President Yoon will bear the blame.
The agency KCNA described the exchange of letters between Moon and Kim as a "sign of deep trust" between the two heads of state.