President Joe Biden is expected to use his final meeting with China’s President Xi Jinping to urge him to dissuade North Korea from further deepening its backing of Russia’s war on Ukraine.

US President Joe Biden told the leaders of Japan and South Korea that their coordinated efforts were essential to “countering North Korea’s dangerous and destabilizing cooperation with Russia” as they met Friday on the sidelines of the APEC Summit in Lima.

The recently signed mutual defense treaty could be used to justify thewidening of the war in Ukraine, as the U.S. says North Korean and Russian troops are already battling Ukrainian forces.