South Korea's foreign minister Cho Tae-yul and US Secretary of State Antony Blinken have jointly criticized the new treaty between Russia and North Korea, calling it a serious threat to regional peace and stability, according to a statement from Seoul's foreign ministry on Friday.

In a phone call on Thursday, Cho and Blinken discussed their concerns over the pact and agreed to closely monitor the situation, the ministry added.

The treaty, announced by Moscow and Pyongyang, stipulates that each country would provide immediate military support in case of armed aggression against the other.

Secretary Blinken affirmed that the United States stands behind South Korea's responses to the treaty. He emphasized that any actions to bolster North Korea's military capabilities would violate UN Security Council resolutions, as stated in the ministry's release.

Blinken also stated that the US would explore various measures to counteract the threat posed to international peace and stability by Russia and North Korea.

South Korean National Security Adviser Chang Ho-jin further announced on Thursday that Seoul is considering the possibility of supplying weapons to Ukraine in response to the landmark treaty.

Recently, tensions between North and South Korea escalated once more when North Korea repeatedly sent trash into South Korean territory using inexpensive balloons.

According to Yonhap news agency's report on Friday, South Korea's military fired warning shots on Thursday morning after several North Korean soldiers crossed the border. The Joint Chiefs of Staff (JCS) confirmed that the soldiers retreated immediately after the shots were fired.

The soldiers had crossed the Military Demarcation Line in the demilitarized zone (DMZ) around 11 a.m. local time on Thursday. This marks at least the third such incident this month. Earlier in the week, on Tuesday, South Korea's military also fired warning shots when a group of North Korean soldiers breached the demarcation line.

This incident occurred shortly after Russian President Vladimir Putin's historic visit to Pyongyang, his first in 24 years.

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