North Korea Cuts Ties, Fortifies Border with South

North Korea's military announced it will implement a "substantial military measure" to fully isolate its territory from South Korea on Wednesday, following months of strengthening its heavily fortified border.

The declaration, coming after North Korean leader Kim Jong Un abandoned a longstanding policy of pursuing peaceful reunification with South Korea earlier this year, stated that remaining roads and railways linked to the South would be completely severed, blocking access along the border.

"The tense military situation on the Korean peninsula necessitates that the armed forces of the DPRK take a more decisive and robust measure to more credibly safeguard national security," the General Staff of the Korean People's Army (KPA) stated, according to a notice on state-run news agency KCNA that referred to North Korea by the acronym for its official name, the Democratic People's Republic of Korea.

Since January, Pyongyang has bolstered its border defenses, planting land mines, constructing anti-tank barriers and dismantling railway infrastructure, according to the South Korean military.

Kim has also escalated his inflammatory rhetoric against the South, labeling it as the North's "primary foe and invariable principal enemy," a description mirrored in the latest KPA notice.

The General Staff stated the measures were in response to recent "war exercises" conducted in South Korea and visits by US strategic nuclear assets to the region. Over the past year, a US aircraft carrier, amphibious assault ships, long-range bombers and submarines have visited South Korea, eliciting angry condemnations from Pyongyang.

Hong Min, a senior research fellow at the Korea Institute for National Unification in Seoul, stated North Korea's latest move formalizes work already underway along its militarized border and suggests Pyongyang may aim to constitutionalize it in the future.

"If North Korea were to establish a new territorial clause through constitutional amendment and sever relationship with the South, the internal and external repercussions would be so great," Hong told CNN. "It seems North Korea is trying to approach this by adjusting the degree."

Rising tensions

Inter-Korean hostilities have intensified this year as North Korea appears to have accelerated its nuclear production efforts and strengthened ties with Russia, deepening widespread concern in the West over the isolated nation's trajectory.

Last week, Kim threatened to employ nuclear weapons to annihilate South Korea if attacked, after South Korea's president warned that if the North used nuclear weapons it would "face the end of its regime."

Kim's remarks seemed to come as a direct response to South Korean President Yoon Suk Yeol, who displayed Seoul's most powerful ballistic missile and other weapons designed to deter North Korean threats during a parade for Armed Forces Day on October 1.

Leif-Eric Easley, a professor at Ewha Womans University in Seoul, stated the Korean army's announcement could be Pyongyang's attempt to "shift blame for its economic failures and legitimize its costly buildup of missiles and nuclear weapons" by exaggerating external threats.

"Kim Jong Un wants domestic and international audiences to believe he is acting out of military strength, but he may actually be motivated by political weakness," Easley stated. "North Korea's threats, both real and rhetorical, reflect the regime survival strategy of a hereditary dictatorship."

North and South Korea have been divided since the Korean War concluded in 1953 with an armistice agreement. The two sides remain technically at war, but both governments had long pursued the goal of eventual reunification.

In January, Kim stated North Korea would no longer seek reconciliation and reunification with South Korea, describing inter-Korean relations as "a relationship between two hostile countries and two belligerents at war," KCNA reported at the time.

In its statement, the North Korean army stated it notified US forces on Wednesday morning to "prevent any misjudgment and accidental conflict" regarding its "fortification project."

CNN has reached out for comment to the United Nations Command, a multinational military force tasked with securing the heavily fortified DMZ between the two Koreas.

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