North Korea will sever road and railway access to South Korea from Wednesday in a bid to “completely separate” the two countries.

Its military said the North would “permanently shut off and block the southern border” and fortify areas on its side.

The Korean People’s Army (KPA) described the move as “a self-defensive measure for inhibiting war”, claiming it was in response to war exercises in South Korea and the frequent presence of American nuclear assets in the region.

It marks an escalation of hostility at a time when tensions between the Koreas are at their highest point in years.

“The acute military situation prevailing on the Korean peninsula requires the armed forces of the DPRK (Democratic People’s Republic of Korea) to take a more resolute and stronger measure in order to more creditably defend the national security,” the KPA said in a report published by state media outlet KCNA.

The declaration is a largely symbolic step by Pyongyang. Roads and railways leading from North Korea to the South are rarely used, and have been incrementally dismantled by North Korean authorities over the past year.

It also comes amid a broader push by Pyongyang to change how it relates to the South, and follows a string of inflammatory incidents that have wounded relations between the two countries.

Those incidents have ranged from missile tests to hundreds of trash balloons being sent over North Korea’s southern border.

Notably, North Korean ruler Kim Jong-un announced at the start of 2023 that he was no longer striving towards reunification with the South, raising concerns that war could resume in the Korean peninsula.

“I think it is necessary to revise some contents of the Constitution of the DPRK,” Kim said at a meeting of North Korea’s Supreme People’s Assembly (SPA) in January.

“In my view, it is necessary to delete such expressions in the constitution as ‘northern half’ and ‘independence, peaceful reunification and great national unity,’” he added, suggesting that the constitution should be revised “at the next session.”

That next session was held this week, and concluded on Tuesday. Yet while many onlookers had expected Pyongyang to ratify Kim’s earlier comments and make constitutional amendments to unification and border policies, no such changes were publicised.

One analyst at the Korea Institute for National Unification suggested that Pyongyang could be waiting for the outcome of the US election before making any concrete decisions.

Officials could “consider adjusting the extent of constitutional revisions to align with the direction of the new (US) administration”, Hong Min told news agency AFP.

It is unclear whether North Korea’s decision to cut off all roads and railways linking it to the South was a result of discussions during the SPA session.