Japan, the United States and South Korea are planning to hold a foreign ministers' meeting in Washington around March 16 to discuss recent agreements between North and South Korea, diplomatic sources said Wednesday.

The planned meeting follows talks this week in Pyongyang between North Korean leader Kim Jong Un and envoys of South Korean President Moon Jae In, at which the South Korean government said Kim expressed readiness for dialogue with the United States.

For Japan and the United States, the meeting is aimed at warning South Korea of their concerns that North Korea's overtures to the Moon administration could compromise the effectiveness of sanctions imposed on the North, the sources said.

Japanese Foreign Minister Taro Kono, U.S. Secretary of State Rex Tillerson and South Korean Foreign Minister Kang Kyung Wha are expected to display their unity in maintaining pressure on North Korea while continuing to push for the denuclearization of the Korean Peninsula.

South Korea's Yonhap News Agency reported Thursday that Kang is planning a visit to the United States next week.

According to a U.S. government official, the trilateral meeting will allow the three countries to align their North Korea policies with each other following a briefing from Moon's envoys about the content of the inter-Korean talks.

Two of the envoys traveled to Washington on Thursday to deliver their briefing. One is then expected to move to Tokyo to brief Japanese officials.

Among the South Korean government's announcements about the Pyongyang talks was North Korea's assertion that it has no reason to possess nuclear weapons if its security is guaranteed.

The governments of Japan and the United States have already discussed the pledge, agreeing it does not make clear whether North Korea is definitely abandoning nuclear weapons, according to the sources.

Tokyo and Washington have also agreed that even if North Korea has promised not to use its nuclear or conventional weapons against South Korea, as reported by the South Korean government, its stance on using them against other countries remains unchanged.

But in order to maintain the momentum toward dialogue between the United States and North Korea, next week's meeting may also involve discussions on how to proceed with the leaders' summit between North and South Korea planned for the end of next month, the sources said.