STORY: Pope Leo on Sunday (April 26) warned of the risks of "increasingly powerful technologies," as Ukraine commemorated the 40th anniversary of the world's worst nuclear disaster, amid lingering fears that Russia's four-year-old war could spark a repeat of the tragedy.

In his Sunday address after the Regina Caeli, a prayer recited between Easter Sunday and Pentecost, the pontiff said the Chornobyl accident had left a mark on humankind's collective conscience.

"I hope that at all decision-making levels, wisdom and responsibility always prevail, so that atomic power can always be used to support life and peace," the pope, who has just returned from a 10-day tour across four African nations, said.

Speaking from the window of the Apostolic Palace, the pope also described as thieves those who, "by plundering the Earth's resources, waging bloody wars, do nothing but rob all of us of the possibility of a future of peace and serenity."

Leo, the first U.S. pontiff, has attracted the ire of President Donald Trump after becoming more outspoken against war and despotism.

DESCRIPCIÓN DE IMÁGENES

SHOWS: VATICAN CITY (APRIL 26, 2026) (VATICAN MEDIA - Access all)

1. CROWD IN ST PETER'S SQUARE

2. SOUNDBITE (Italian) POPE LEO SAYING:

"Even those thieves who, by plundering the Earth's resources, waging bloody wars, or fuelling evil in any form, do nothing but rob all of us of the possibility of a future of peace and serenity. We may ask ourselves: Who do we want to guide us in our life? Which thieves have tried to enter our enclosure? Did they succeed or were we able to repel them?"

3. CROWD LISTENING TO PRAYER

4. SOUNDBITE (Italian) POPE LEO SAYING:

"Today marks the fortieth anniversary of the tragic Chornobyl accident, which left a mark on humanity's conscience. It remains a warning about the risks inherent in the use of increasingly powerful technologies. We entrust to God's mercy the victims and those who still suffer from its consequences."

5. CROWD CHEERING

6. SOUNDBITE (Italian) POPE LEO SAYING:

"I hope that at all levels of decision-making, discernment and responsibility will always prevail, so that every use of atomic energy may be at the service of life and peace."

7. CROWD APPLAUDING

8. BELLS OF ST PETER'S BASILICA RINGING