This image captured from the Center for Strategic Communication and Information Security of Ukraine shows soldiers appearing to be North Koreans receiving what appears to be Russian military supplies. (Yonhap)

A South Korean government delegation to Ukraine returned home Monday after visiting Kyiv to discuss possible cooperation measures in response to North Korea's troop deployment to Russia, officials said.

The delegation, consisting of senior intelligence and military officials, visited Ukraine after briefing the North Atlantic Treaty Organization in Brussels last week over the North's troop dispatch.

The visit came as South Korea has signaled a potential shift in its Ukraine support policy following reports that Pyongyang has sent thousands of soldiers to fight alongside Moscow in the war against Kyiv.

Speaking to reporters Wednesday in Washington, D.C., Defense Minister Kim Yong-hyun said: "(We) will take necessary measures in cooperation with the international community, based on reports from the group," he said.

Kim appeared to be referring to Seoul's consideration of sending a team of observers to Ukraine to monitor North Korean troops deployed in support of Russia.

On Friday, National Security Adviser Shin Won-sik told lawmakers in a parliamentary audit that such a dispatch would be essential for South Korea to understand modern warfare.

If sent, the team of observers is expected to be composed of military and intelligence personnel, and could possibly take part in analyzing North Korean combat tactics and interrogations of captured troops.

Amid growing concerns of North Korean troops possibly joining combat against Ukraine, South Korea has vowed to take "phased measures" in response to the level of military cooperation between Russia and North Korea.