Secretary-General Antonio Guterres says he is encouraged by the improvement of relations between the two Koreas, but the U.N.'s objective is the peaceful denuclearization of the Korean peninsula.

The U.N. chief told reporters Friday that he was "especially encouraged" by the re-establishment of a military hotline between North Korea and South Korea "to avoid situations that get out of control."

But Guterres stressed that such steps are "just part of the problem."

As for denuclearization, he said that "it is absolutely essential that serious discussions take place among the key actors in this process, and the U.N. will do everything possible to encourage them in that regard."

Guterres added: "We believe that the unity of the Security Council is creating the conditions for that to be achieved in diplomatic engagement."