Pope Leo appealed for authorities in Iran and Israel to act with "reason" after airstrikes between the two countries, and called on the nations to pursue dialogue.
Leo told an audience in St. Peter's Basilica he was following the situation with "great concern."
"In these days, news continues to arrive that causes great concern: the situation in Iran and Israel has seriously deteriorated. At such a delicate moment, I wish to strongly renew an appeal to responsibility and reason," the pope said.
He stressed that the nuclear security must be pursued through respectful encounters and sincere dialogue to build a lasting peace.
The pope urged to support the cause of peace, initiating paths of reconciliation and promoting solutions that guarantee security and dignity for all.
Israel launched a large-scale attack on Iran early on Friday, targeting commanders, military targets and nuclear sites. Iran retaliated by launching waves of missiles at Israel.