Foreign Minister Kang Kyung-wha and her U.S. counterpart Secretary of State Mike Pompeo held talks in New York on Friday.
The two last met 12 days ago in Tokyo following Pompeo's visit to North Korea.
The New York meeting was also attended by Seoul's Permanent Representative to the United Nations Cho Tae-yul and U.S. Ambassador to the UN Nikki Haley.
Kang and Pompeo are known to have coordinated communication on North Korea's denuclearization talks and ways to advance South Korea-U.S. relations.
The two briefed each other on the dialogue each side has conducted with Pyongyang since their Tokyo meeting.
Before the meeting with Pompeo, Kang told reporters that North Korea has repeatedly made a "clear commitment" to complete denuclearization, and that "we will hold them up to that commitment."
After their meeting, Kang and Pompeo gave a joint briefing to representatives of the 15 UN Security Council member nations.
Kang told the UN briefing that any easing of sanctions must be preceded by steps toward denuclearization.