NextFin news, South Korean military intelligence has reported that Russia may have supplied North Korea with nuclear reactor modules intended for use in submarines, according to information revealed on Thursday, September 18, 2025.
The intelligence suggests that in the first half of 2025, Russia delivered two or three submarine modules to North Korea. These modules reportedly include a nuclear reactor, turbine, and cooling system — essential components for a nuclear-powered submarine. The modules are believed to have been sourced from decommissioned Russian submarines rather than newly manufactured equipment.
Government sources in South Korea stated that North Korea has been actively seeking nuclear submarine technology from Russia since last year. Initially, Russia resisted these requests but appears to have agreed to supply the technology this year.
North Korea prioritizes the construction of nuclear-powered submarines as a strategic goal, viewing them as a critical component to complete its nuclear forces capable of striking the United States. On March 8, 2025, North Korea’s state newspaper Rodong Sinmun published photos showing leader Kim Jong-un inspecting what appears to be a strategic nuclear-powered submarine under construction.
Experts note that North Korea lacks the domestic technical capacity to develop small nuclear reactors suitable for submarines, making the acquisition of Russian modules a significant leap in its capabilities.
Reports also indicate that North Korea may have pressured Moscow to provide this technology in exchange for sending North Korean troops to support Russian military operations in Ukraine.
If confirmed, this transfer would constitute a serious violation of the Nuclear Non-Proliferation Treaty (NPT) and could trigger additional international sanctions against both North Korea and Russia.
South Korea has shared this intelligence with the United States and allied countries as part of ongoing efforts to monitor and respond to nuclear proliferation risks in the region.
Explore more exclusive insights at nextfin.ai.