RELIGIOUS leaders in Ukraine have marked the 40th anniversary of the Soviet-era Chernobyl nuclear disaster, which cost an estimated 16,000 lives and £516 billion in global environmental damage.

“Ukraine marks this anniversary in the fifth year of the full-scale war unleashed by the Russian Federation, whose regime is the moral successor of the authoritarian Soviet dictatorship responsible for the Chernobyl tragedy,” the Ukrainian Council of Church and Religious Associations said.

“The territory of Ukraine has become the world’s most contaminated, with mines, unexploded ordnance, and explosives. . . In this context, we call on the international community to take decisive action to prevent a new nuclear tragedy.”

In a message released on Sunday, the Council said that greater damage had been prevented only by the “heroism” of emergency responders, but warned that Russia’s current occupation of Ukraine’s Zaporizhzhia nuclear power plant also threatened “new global-scale disasters”.

Reactor 4 of the Chernobyl plant exploded during a power surge on 26 April 1986, releasing radioactive contaminants across the then Soviet Union and Eastern Europe, and forcing the evacuation of more than 100,000 people from a 22-mile exclusion zone.

Although a steel and concrete sarcophagus was constructed over the destroyed reactor to enable a final clean-up, scheduled for completion by 2065, this was shelled in February 2025 by Russian invasion forces.

Wreaths and candles were placed at the Chernobyl National Monument on Sunday by President Zelensky, during a commemoration attended by the secretary-general of the International Atomic Energy Agency, Rafael Grossi.

Addressing pilgrims in Rome, the Pope said that the disaster had “left a lasting mark on the conscience of humanity”, and that he hoped that “discernment and responsibility” would ensure that atomic energy was “placed at the service of life and peace”.

The Primate of the Orthodox Church of Ukraine (OCU), Metropolitan Epiphany (Dumenko), paid tribute to those who died fighting the disaster and later from lethal radiation, but also warned that Russian attacks continued to imperil nuclear safety.

The Chernobyl disaster, he said, had been caused by a Soviet system which “militarised science” and proved “irresponsible about safety”, and which delayed critical reactions by concealing its “scale and consequences”.

“Millions felt and continue to feel the consequences of the accident,” Metropolitan Epiphany said in a sermon on Sunday. “The lesson of Chernobyl should be a deeper awareness that science and progress have their limitations, and should not be separated from moral responsibility to both people and the natural environment.”