In this image, President Donald Trump shows the document he and North Korea's leader Kim Jong Un signed acknowledging the progress of the talks and pledge to keep momentum going, after their summit at the Capella Hotel on Sentosa island in Singapore, June 12, 2018. REUTERS/Jonathan Ernst/File Photo

In order to follow-up on denuclearization negotiations, the United States and North Korea are coordinating a top American diplomat's visit to Pyongyang, Seoul's foreign ministry said Tuesday. The ministry also restated its goal to achieve the declaration of a formal end to the Korean War by this year.

"During the future negotiations (between the U.S. and the North), the concrete sequence of the denuclearization process, ways to guarantee the North's security and the normalization of U.S.-North Korea relations in conjunction with denuclearization are expected to be at issue," the South Korean ministry said in its parliamentary briefing Tuesday.

While referring to the April inter-Korean summit declaration, the ministry said the government’s goal “is to achieve the end-of-war political declaration this year when we mark the 65th anniversary of the signing of the armistice agreement,” Yonhap News Agency reported.

As part of the negotiations, U.S. National Security Advisor John Bolton said Sunday, that Secretary of State Mike Pompeo would soon travel to the communist state for a fourth visit.

"This week, I think Secretary Pompeo will be returning to Pyongyang soon for his fourth visit,” he said, adding, "I think the timing will be announced at an appropriate point by the State Department. .. To move on with the process of denuclearization remains our highest priority. … it's important that they (the DPRK) demonstrate seriousness,” according to Xinhua Net.

Recently, Reuters reported about Washington's reluctance to declare an end to the Korean War until Pyongyang took tangible steps toward denuclearization.

A commentary in Rodong Sinmun, the official newspaper of the Central Committee of the Workers' Party of North Korea read: "There is no reason to ignore a declaration to end the war. It is a preliminary and essential process to pave the ground for detente and permanent peace on the Korean Peninsula.”

“The U.S. should implement phased and simultaneous measures, like the end-of-war declaration, to build mutual trust and make a breakthrough in the security of the world," the paper said.

Earlier this month, North Korea had threatened to stall denuclearization talks as it accused U.S. officials of making baseless allegations despite Pyongyang’s goodwill moves.

"As long as the U.S. denies even the basic decorum for its dialogue partner... one cannot expect any progress in the implementation of the DPRK-US joint statement including the denuclearization ... both sides should make efforts to settle the problems,” a foreign ministry spokesperson said.

Commenting on the same, North Korea’s foreign minister Ri Yong Ho said, “Since we know that the U.S. will never give up its hostile policy toward us, we will hold on to our nuclear knowledge,” the Guardian reported.

During the historic June summit in Singapore, the two nations agreed to work to establish “new” ties with each other.

A joint statement at the end of the summit said, "President Trump committed to provide security guarantees to the DPRK and Chairman Kim Jong Un reaffirmed his firm and unwavering commitment to complete denuclearization of the Korean Peninsula.”