North Korea announced on Monday that it successfully conducted a static ground test of a new high-thrust solid-fuel rocket engine designed for its intercontinental ballistic missiles (ICBMs). The test, personally overseen by leader Kim Jong Un, took place at an undisclosed location, according to the state-run Korean Central News Agency (KCNA).
Pyongyang described the engine as the most powerful yet developed by the country. If fully operational, the technology would represent a significant leap in North Korea’s missile program. Solid-fuel designs provide major strategic advantages over liquid-fuel systems, as they can be pre-fueled, stored, and launched on short notice. This reduces preparation time, increases mobility, and makes detection by adversaries far more difficult. Unlike liquid-fuel rockets, which often require lengthy fueling operations at fixed sites, solid-fuel missiles can be transported in concealed vehicles and launched from diverse locations.
The engine is intended for the Hwasong-20, North Korea’s latest ICBM model, which analysts say could be capable of striking the U.S. mainland. Experts believe this test clears the way for a possible full-range ICBM flight trial before the end of 2025.
The development has prompted concern and condemnation from the United States, South Korea, and Japan. Officials in Seoul and Tokyo warned that advances in solid-fuel missile technology increase the risk of surprise attacks and complicate missile defense planning. Washington has emphasized the growing threat North Korea poses to regional and international security.
This marks the fourth missile-related test by North Korea in the past six weeks, highlighting the regime’s accelerated weapons program. On July 30, Pyongyang fired a medium-range ballistic missile (MRBM), believed to be a Hwasong-12 variant, from a mobile launcher. On August 12, the country launched a submarine-launched ballistic missile (SLBM) from a submerged submarine in the Sea of Japan, the first such test in over six months. Two weeks later, on August 28, North Korea launched around ten short-range ballistic missiles toward the Sea of Japan, described by KCNA as “tactical guided weapons.”
Analysts suggest that North Korea’s renewed partnership with Russia has been a key factor in these advancements. Following a rapprochement in 2023 and the signing of a military alliance last year, Moscow is believed to have provided technical support and expertise, including assistance in developing advanced solid-fuel systems.