President Yoon Suk Yeol (second from right) attends a session of the Group of 20 summit in Rio de Janeiro, Brazil, on Monday. (Yonhap)

President Yoon Suk Yeol strongly condemned the deepening military cooperation between North Korea and Russia at the Group of 20 summit in Brazil on Monday, Yoon's office said.

Yoon used the G20 sessions to urge Pyongyang and Moscow to immediately cease their "illegal" military cooperation and called for international unity to issue a stern warning against such moves, Principal Deputy National Security Adviser Kim Tae-hyo said.

The condemnation by Yoon came shortly after Russian Foreign Minister Sergey Lavrov, who attended the G20 session on behalf of President Vladimir Putin, made remarks.

Japanese Prime Minister Shigeru Ishiba, Canadian Prime Minister Justin Trudeau, and Australian Prime Minister Anthony Albanese joined Yoon in criticizing North Korea's involvement in Russia's war against Ukraine, expressing concerns over its broader implications for global security, a senior presidential official said. (Yonhap)