The massive steel shelter built to contain the radioactive ruins of the Chernobyl nuclear power plant can no longer perform its primary safety function following an attack by Russia earlier this year, the United Nations' atomic energy watchdog has confirmed.
Attack Compromises Critical Safety
A suspected Russian drone strike hit the site in northern Ukraine in 2025, igniting a fire in the outer cladding of the structure known as the New Safe Confinement. The immense arch was slid over the destroyed reactor in 2016 to seal in hazardous material from the 1986 disaster. The strike immediately raised alarms about a potential radioactive leak threatening Ukraine and wider Europe.
The International Atomic Energy Agency (IAEA) has now assessed that the shelter's structure has degraded. It stated that the steel confinement has lost its 'primary safety functions', specifically the crucial ability to confine radioactive material. However, the agency noted that no permanent damage was found in the load-bearing structures or the monitoring systems.
Urgent Repairs and Long-Term Concerns
IAEA Director General Rafael Grossi reported that limited temporary repairs have been made to the roof. He emphasised, however, that 'timely and comprehensive restoration remains essential to prevent further degradation and ensure long-term nuclear safety.'
The nuclear watchdog outlined necessary work, which includes:
- Implementing humidity control measures.
- Updating the corrosion monitoring programme.
- Upgrading the integrated automatic monitoring system for the shelter.
The IAEA said temporary repairs are planned for 2026 to ensure radioactive material is contained. A 'full restoration' is dependent on the end of the war between Russia and Ukraine. A team from the agency remains permanently stationed at the site.
Broader Nuclear Safety Mission in Ukraine
In a related development, the IAEA began a 12-day visit to Ukraine on Monday, 6 December 2025. The mission aims to assess the status of electrical substations critical for nuclear safety and security after recent military attacks on energy infrastructure.
More than ten substations, which are vital for powering nuclear plants' cooling and safety systems, will be reviewed for damage and repairs. Grossi stressed these facilities are 'absolutely indispensable' for safe reactor operation and for distributing electricity. Previous inspections have noted a continued degradation of the power grid.
'The IAEA will continue to do everything it can to support efforts to fully restore nuclear safety and security at the Chornobyl site,' Grossi affirmed.
