Ukraine marked the 40th anniversary of the Chernobyl nuclear disaster on Sunday, with solemn commemorations overshadowed by President Volodymyr Zelenskyy's stark accusation against Russia.

In a Telegram post, Zelenskyy stated that Russia, through its ongoing invasion, is "once again putting the world on the brink of a man-made disaster." He highlighted Russian-Iranian Shahed drones that "constantly fly over the plant," noting one struck the containment structure last year. "The world must not allow this nuclear terrorism to continue, and the best way to do so is to force Russia to stop its insane attacks," he urged.

Zelenskyy also signed decree No. 341/2026, awarding state honors to 92 individuals involved in the Chernobyl response. The honors, including Orders of Prince Yaroslav the Wise and For Merit, recognize their contributions to mitigating the disaster's aftermath.

The president visited the Chernobyl power plant with officials and paid respects at a victims' memorial alongside Moldova's President Maia Sandu. In Slavutych, the city built for plant workers, residents gathered at midnight on Saturday, laying flowers and holding candles at memorials to firefighters and liquidators who perished.

The 1986 explosion at Reactor 4, triggered by errors during a safety test, released massive radioactive material across Ukraine, Belarus, Russia, and Europe. Around 600,000 liquidators contained the fallout at great personal risk. A concrete sarcophagus and later New Safe Confinement arch, funded internationally, now shield the site.

Russia briefly occupied Chernobyl in February 2022 at the invasion's outset. Concerns escalated after a drone hit the protective arch in February 2025, compromising safety features. International Atomic Energy Agency head Rafael Grossi, visiting Kyiv, called for immediate repairs costing at least 500 million euros to avert further risks.

Russian strikes intensified around the anniversary. Ukraine downed 124 of 144 drones overnight, but attacks killed at least three people and wounded four others. Broader exchanges reported at least 16 deaths across Ukraine and Russian-held areas.

Zelenskyy concluded his message honoring the victims: "We remember everyone who gave their lives while dealing with the aftermath of this tragedy. May the memory of all the victims of the Chernobyl disaster live on."