As the circumstances in which North Korea provided weapons to Russia have come to light, the possibility of Russia providing North Korea with cutting-edge defense materials or military technologies in return is looming.

If Russia transfers technologies necessary to perfect North Korea's ballistic missiles, it will seriously violate United Nations sanctions against the North and greatly undermine stability on the Korean Peninsula.

White House national security spokesperson John Kirby said on Friday that the United States believes North Korea provided more than 1,000 containers of military equipment and munitions in recent weeks to Russia for use in Ukraine.

According to a series of satellite images the White House disclosed, North Korea handed over containers of military supplies to a Russian-flagged ship, and they were taken by rail to a depot near Russia's southwestern border. The delivery took place between Sept. 7 and Oct. 1.

North Korea might have provided the large support because it was promised something in return. The images show related decisions had been made before North Korean leader Kim Jong-un departed on Sept. 10 for Russia's Far East for a summit with Russian President Vladimir Putin.

If the US assessment is true, Russia's behavior constitutes the violation of UN Security Resolution No. 1,874, which bans all weapons exports from North Korea.

But Oleg Burmistrov, a Russian ambassador at large, said Sunday that Russia, as a responsible member of the world community, strictly adheres to its international obligations concerning Pyongyang through the UN Security Council. Russian Foreign Minister Sergey Lavrov said last month that sanctions against North Korea were declared by the United Nations Security Council, not Russia. It is hard to expect change in Moscow's position on North Korea.

It is also not easy for the UN Security Council to levy additional sanctions against North Korea over its arms deal with Russia, because Russia and China will likely veto them. Different sanctions than before are needed to prevent further exchanges between Moscow and Pyongyang. First, South Korea, the United States and Japan will have to strengthen their individual and joint sanctions.

On Sept. 13 when the Kim-Putin was held, Kremlin said it would cooperate with North Korea in "sensitive areas that can't be disclosed." If Russia helps North Korea complete the development of high-tech weapons systems such as nuclear-powered submarines and spy satellites, they could be game-changing weapons for North Korea. If Russia transfers technology for atmospheric reentry of an intercontinental ballistic missile, it will pose a grave threat not only to South Korea, but also to the US. This is why South Korea's President Yoon Suk Yeol in his address to the UN General Assembly defined the Russo-North Korean military exchange as a direct provocation of South Korea.

A deal that threatens the life of the South Korean people directly is crossing a line in the relationship between South Korea and Russia. The government should give a warning to Moscow and take every possible self-defense measure. It will have to make the best use of its diplomatic leverage to prevent Russo-North Korea ties from crossing the line.

It is also important to persuade Russia through direct diplomatic contact, while working out response strategies with Washington. However, depending on the circumstances, Seoul may have to take a strong diplomatic stance toward Moscow.

The government must grasp what Russia has provided or is providing to North Korea. Reliance on US reconnaissance is inevitable, but South Korea must exert every effort to acquire information independently. It should fully mobilize its informational strength.

If the worst fears about military exchanges between Russia and North Korea are found to be reality, the government must seek strong joint responses with the international community. It must let the world know that the two countries are undermining the security of Northeast Asia, and strengthen its security network with the US and allies.