Top nuclear envoys of South Korea, the United States and Japan met Tuesday to discuss cooperation against North Korea's growing nuclear and missile threat.

Kim Hong-kyun, special representative for Korean Peninsula peace and security affairs at the ministry, held talks with his US and Japanese counterparts, Joseph Yun and Kenji Kanasugi, at a hotel in Seoul.

"I think it is indeed meaningful that at this time our three countries are meeting again to have an in-depth discussion on how to further strengthen our trilateral coordination on North Korea," Kim told his counterparts before the meeting started.

"Given the seriousness of the situation unfolding in the region, I cannot emphasize enough the importance of maintaining close coordination between the three countries," he added.

They got together to discuss how to implement a new set of sanctions adopted by the United Nations Security Council last month to punish the North for its fifth nuclear test in September. In a follow-up move, the three countries unveiled their own unilateral sanctions later on.

Yun reassured the US support for the UNSC's latest Resolution 2321, which mainly focuses on restricting the North's coal exports deemed to be a major source of hard currency for its nuclear and missile programs.

"The US welcomes the recent adoption of UNSC Resolution 2321 and, of course, our three countries coordinated very closely together in announcing our unilateral sanctions," the US negotiator said. "This harmonization of our own sanctions, as well as working together in New York, really shows and symbolizes our strong trilateral cooperation on North Korea."

Kanasugi, meanwhile, emphasized that the meeting was held "in a very timely manner" as it came after the three announced their respective unilateral measures against the North.

"I believe, by doing so, in a very coordinated way, we are able to send our strong message to the DPRK, in particular, and to the international community as a whole," he said. (Yonhap)