South Korea is considering direct arms sales to Ukraine as evidence mounts that North Korean soldiers are preparing to support Russia in its war against Ukraine.

South Korea's spy service (NIS) said last week that North Korea had sent 1,500 special forces to Russia's Far East to train and acclimatize at local military bases in order to fight alongside Moscow's troops in Ukraine in the future.

Local media, citing the NIS, said Pyongyang had decided to send 12,000 troops to Russia, divided into four brigades.

A senior official in the office of South Korean President Yoon Suk Yeol said on Tuesday that Seoul could consider supplying defense and lethal weapons to Ukraine, depending on developments.

“We would consider supplying weapons for defense purposes as part of the tiered scenarios, and if it appears that they go too far, we could also consider offensive use,” the presidential official told reporters, echoing Seoul's most proactive stance on arming Ukraine to date.

The development underscores the potential for a divided Korean peninsula to become embroiled in the conflict.

The president's comments came after South Korea's National Security Council held an emergency meeting to consider its responses to North Korea's increasing military ties with Russia.

South Korea, which has some of the world's largest stockpiles of artillery shells, has provided humanitarian aid and other support to Ukraine while joining Western-led economic sanctions against Moscow.

However, the country has not directly supplied Kiev with weapons, citing its long-standing policy of not supplying weapons to countries actively involved in conflict.

Seoul's policy change would be welcomed by Kiev, which is facing a desperate shortage of ammunition. Ukrainian President Volodymyr Zelensky previously called for a “strong response” from international partners to North Korea’s involvement in the ongoing war.

Meanwhile, a number of clips have emerged in recent days reportedly showing North Korean soldiers training in Russia.

On Sunday, Ukraine's Center for Strategic Communications and Information Security distributed a video that appeared to show North Korean soldiers receiving uniforms and equipment at the Sergeyevka military training area in Russia's far east.

Astra, an independent Russian broadcaster, released two clips on Tuesday showing what appeared to be North Korean soldiers standing in front of a military base. The men can be heard speaking in Korean while an instructor tells the soldiers to “come into the building.”

Independent researchers geolocated the clips to the Sergeevka training ground.

The Kremlin refused to directly answer a question about whether or not North Korean troops would fight in Ukraine, but said it was Moscow's sovereign right to establish relations with Pyongyang in all areas.

North Korean leader Kim Jong-un and Russian President Vladimir Putin, who met for the first time in 2019, are seeking greater military and economic cooperation to counter their growing international isolation caused by Russia's invasion of Ukraine and North Korea's ballistic missiles and nuclear weapons was caused by weapons programs. In June, the two leaders signed a pact that includes a clause requiring the countries to help each other if either country is attacked.

The United Kingdom said on Monday that it “considers it highly likely that North Korea has agreed to send troops to support Russia's war in Ukraine.”

“It seems that the harder it is for Putin to recruit Russians as cannon fodder, the more willing Putin is to rely on the DPRK (North Korea) in his illegal war,” said Dame Barbara Woodward, the British permanent representative to the United Nations. said during a speech in New York.

“Putin is obviously desperate. His desperation is a danger to us all.”