North Korea has accused South Korea of fabricating a landmine explosion that injured three South Korean soldiers, according to a letter sent to the United Nations Security Council (UNSC). The accusation, reported by North Korea's Korean Central News Agency, claims the incident was a "sinister obstructive move" orchestrated by Seoul.

The North Korean permanent representative to the UN wrote to the UNSC on Sunday, denouncing the "provocation the ROK [Republic of Korea] committed by groundlessly shifting the blame for the dubious ‘mine explosion incident’". The letter warned that such violations of North Korea's sovereignty could lead to self-defense actions.

Tensions between the two Koreas have recently escalated following an explosion inside the Demilitarized Zone (DMZ) on September 21. South Korea had blamed North Korean landmines for the blast, an accusation Pyongyang has vehemently rejected. North Korea's UN representative described the claims as a "farce to evade the responsibility for the ever-escalating tensions on the Korean peninsula."

The North Korean letter asserted that the country's ongoing border fortification efforts are a "legitimate and just exercise of its sovereignty going in strict conformity with the UN Charter." It also criticized South Korea for allegedly violating the charter by firing warning shots at North Korean soldiers who crossed the Military Demarcation Line (MDL) within the DMZ.

South Korea maintains that it fires warning shots to deter North Korean soldiers from crossing the MDL. In recent years, there has been increased activity by North Korean personnel building tactical roads and fences near the MDL.

This development follows a letter sent by the South Korean Foreign Ministry to the president of the UNSC last week. In that communication, Seoul placed blame on North Korea for the landmine incident, labeling it a "clear violation of the armistice agreement."

The United States-led UN Command has also stated that mine placement by North Korea contravenes the Armistice Agreement, which was signed in 1953 to end hostilities in the Korean War.

Just days before North Korea's letter to the UN, South Korea's Defence Ministry had proposed military talks with Pyongyang. The aim of these discussions was to "mutually confirm the precise location" of their border and thereby reduce the risk of accidental clashes.