Director of South Korea's National Security Office Suh Hoon meets reporters on Oct. 15 after his meeting with U.S. Secretary of State Mike Pompeo at the U.S. Department of State headquarters in Washington, D.C. Yonhap

There exists no difference of opinion between South Korea and the United States on the need to formally end the Korean War as part of the process to denuclearize North Korea, South Korea's national security adviser said, adding it is "common sense" that the two issues go together.

Suh Hoon, director of South Korea's National Security Office, said the only issue was when a declaration of the war's end could or should be made.

"The issue of declaring the war's end is not a new issue. It has always been on the negotiating table and there can be no different views regarding the issue between South Korea and the U.S.," Suh told reporters after his meeting with U.S. Secretary of State Mike Pompeo.

The South Korean official arrived here Tuesday on a four-day visit that the presidential office Cheong Wa Dae said was aimed at enhancing the South Korea-U.S. alliance through close communication between the countries' national security councils.

Suh met his U.S. counterpart, Robert O'Brien, on Wednesday.

His trip here comes after South Korean President Moon Jae-in called for international efforts to officially end the 1950-53 Korean War in his speech at the United Nations General Assembly last month.

Moon said the move would help restart the stalled negotiations on ridding North Korea of its nuclear weapons program by partly providing a security guarantee it has long sought.

South and North Korea technically remain at war as the Korean War ended only with an armistice and not a peace treaty.

Suh Hoon and Mike Pompeo before their meeting at the U.S. Department of State headquarters in Washington, D.C., Oct. 15 Courtesy of Cheong Wa Dae

Some have claimed Seoul seeks to declare the war's end regardless of progress in the North's denuclearization process.