As pressures mounts in the Korean peninsula over weapons tests, North’s leader Kim Jong Un has thanked outgoing South Korean President Moon Jae-in for making concerted efforts to improve relations between the two nations, state media KCNA reported on Friday.  

This rare development comes as several weapons tests have been carried out by Pyongyang since the beginning of this year, including the launch of several intercontinental ballistic missiles (ICBMs) in the past few months.

On Wednesday, Moon had sent a letter to Kim and had promised to keep trying to lay a foundation for unification. The South Korean leader said it will be based on joint declarations, which were reached at summits in 2018, the KCNA news agency said.  

"Kim Jong Un appreciated the pains and effort taken by Moon Jae-in for the great cause of the nation until the last days of his term of office," KCNA said.  

It also said that the exchange was an "expression of their deep trust."  

The "era of confrontation" should be overcome with dialogue and the next administration should look to hold inter-Korean engagement, Moon said in the letter, spokeswoman Park Kyung-mee told a media briefing.   

In reply on Thursday, Kim said their "historic" summits gave people "hope for the future". He also said ties would develop if both sides "make tireless efforts with hope," KCNA reported.

It will, however, remain a challenging task for the new South Korean President to continue the momentum gained from the exchange of goodwill through these letters.