Prime Minister Shigeru Ishiba and South Korean President Yoon Suk Yeol have expressed "strong concerns” over military cooperation between North Korea and Russia, with the pair using a meeting Saturday to push for a “unified message” on the issue.

Ishiba and Yoon held their second in-person meeting in just over a month, this time on the sidelines of the Asia-Pacific Economic Cooperation in Lima, with the pair also pledging to continue "shuttle diplomacy" during their talks, the South Korean Presidential Office said.

But it was North Korea's deployment of more than 10,000 troops to Russia in support of Moscow's war in Ukraine — as well as Pyongyang’s continued missile and nuclear development in defiance of United Nations sanctions — that took top billing in the meeting.