President Yoon Suk Yeol (left) heads to a conference room at a hotel in Lima, Peru on Friday, to meet Chinese President Xi Jinping on the sidelines of the Asia-Pacific Economic Cooperation summit. (Yonhap)

South Korean President Yoon Suk Yeol made an emphatic call for international solidarity against growing military ties between North Korea and Russia and urged the two countries to halt their "reckless" military adventure as he attended the Asia-Pacific Economic Cooperation summit in Peru on Friday.

In a keynote speech, Yoon condemned "illegal" military cooperation between Pyongyang and Moscow as intelligence reports have confirmed that North Korean forces have been engaged in combat alongside Russian troops against Ukrainian forces in the Kursk region.

"The illegal military cooperation between North Korea and Russia is a grave challenge to the international order and undermines APEC's efforts for future cooperation," Yoon was quoted as saying in a summary provided by his office.

"I urge North Korea and Russia to halt reckless military adventure and immediately cease their military cooperation," Yoon said, calling for APEC leaders to deliver a strong message for peace and stability in the region.

Yoon's call came as Ukraine faces the urgent need to beef up its position in the ongoing war as speculation has continued that US President-elect Donald Trump could push for a peace deal that might involve some Ukrainian territorial concessions.

Pyongyang and Moscow have ratified the comprehensive strategic partnership, which includes a mutual defense provision that requires both countries to use all available means to provide immediate military assistance if either is attacked.

At the APEC summit, Yoon also underscored the importance of creating a "free and stable" trade environment, pledging South Korea's leadership in fostering resilient global supply chain ahead of hosting the next year's gathering.

"South Korea plans to identify and expand tailored projects to enhance APEC members' free trade agreement negotiation capabilities, supporting countries in the region to enjoy the benefits of free trade," Yoon said.

He also proposed creative and innovative solutions to address economic inequality, vowing to leverage artificial intelligence and eco-friendly technologies to support inclusive growth across the region.