The massive steel structure built to contain radioactive remnants of the 1986 Chernobyl disaster has lost its core safety functions following a drone strike earlier this year, the United Nations’ nuclear watchdog said, raising new concerns about long-term nuclear security in a region destabilized by nearly four years of war.
In a statement released Friday, the International Atomic Energy Agency (IAEA) said the New Safe Confinement (NSC) — the vast arch-shaped enclosure completed in 2019 to seal off the ruined No. 4 reactor — was “severely damaged” in a February 14 drone strike and can no longer guarantee confinement of radioactive materials. The IAEA did not assign responsibility for the attack, but Ukraine has accused Russia of targeting the structure. The Kremlin has denied involvement.
The strike ignited a fire and destroyed portions of the protective outer cladding, the agency said. While the NSC’s core load-bearing systems and monitoring equipment remain intact, the damage to its enclosure has compromised the structure’s prime purpose: preventing the escape of radioactive dust and enabling ongoing cleanup operations.
“Limited temporary repairs have been carried out on the roof, but timely and comprehensive restoration remains essential to prevent further degradation and ensure long-term nuclear safety,” IAEA Director General Rafael Mariano Grossi said. He added that the agency, which maintains a permanent presence at the site, will continue assisting efforts to stabilize the structure.
Built between 2010 and 2019 at a cost of €2.1 billion, funded by more than 45 donor nations, the NSC was hailed as one of the world’s most ambitious engineering feats — a movable steel hangar designed to last at least a century. Its construction enabled the dismantling of unstable remnants of the original Soviet-era sarcophagus and provided a secure environment for radioactive waste management.
The February strike is the latest incident underscoring the vulnerability of nuclear facilities amid the ongoing conflict. Russian forces seized Chernobyl in the opening days of the 2022 invasion, holding workers hostage before withdrawing weeks later. Although the plant is no longer operational, it remains one of the most closely monitored sites in the world because of the vast quantities of radioactive material stored there.
Nuclear experts caution that a compromised NSC does not pose an immediate catastrophic threat but does increase long-term risks. Without restoration, weather exposure and structural fatigue could accelerate deterioration of the damaged sections, potentially complicating containment efforts in the decades ahead.
The Chernobyl disaster remains the world’s worst civilian nuclear accident. The 1986 explosion released radioactive material across Ukraine, Belarus, Russia and parts of Europe, with lasting health consequences including elevated cancer rates and birth defects among populations exposed to high levels of radiation.
As the war drags on, the situation at Chernobyl highlights the broader challenge of safeguarding critical nuclear infrastructure in active conflict zones — an issue that the IAEA has repeatedly warned carries global implications.