Nuclear envoys and negotiators of South Korea, the United States and Japan met in Tokyo on Thursday to launch a trilateral working group to address the North’s growing cyber threats.

South Korea’s deputy nuclear envoy Lee Joon-il and his counterparts U.S. Deputy Assistant Secretary Jung Pak and Japan’s Deputy Director-General of the Foreign Policy Bureau Hideo Ishizuki vowed to strengthen cooperation to block illegal cyber activities of North Korea that have been a major source of funds for North Korea’s nuclear and missile development, said the Foreign Ministry in Seoul.

“The three evaluated the achievements of cooperation so far and took the launch of the working group as an opportunity to strengthen cooperation countering the North’s cryptocurrency theft, hacking activities and exploitation of its overseas IT workers,” said the ministry.

The group’s establishment follows up on the trilateral agreement reached between the leaders at the Camp David summit in August this year to crack down on the North’s illegal cyber activities.

The issue was expected to be also discussed in the upcoming trilateral meeting on security and intelligence in Seoul on Saturday, to be hosted by National Security Adviser Cho Tae-yong and joined by his counterpart national security advisors Jake Sullivan of the U.S. and Akiba Takeo of Japan.

These meetings followed closely a series of sanctions levied unilaterally by the governments of South Korea, the United States, Japan and Australia against the North last week.

The South Korean government added 11 North Korean nationals who participated in the development of the recently launched spy satellite, including intercontinental ballistic missile experts, to its sanctions list last week.

BY ESTHER CHUNG [chung.juhee@joongang.co.kr]