Pope Leo led the world's Catholics into Easter at a Saturday night vigil Mass in St. Peter's Basilica and urged people not to feel numbed by the scope of the conflicts raging across the world but to work for peace.

Leo, who has emerged as an outspoken critic of the Iran war, said that mistrust and fear have been allowed to "sever the bonds between us through war, injustice and the isolation of peoples and nations."

"Let us not allow ourselves to be paralyzed!" the first U.S. pope exhorted in a service for the holiest night in the Catholic calendar, when the Bible says Jesus rose from the dead.

Leo did not mention any specific conflicts during the service, at which he also baptized 10 adult converts to Catholicism.

In his homily to thousands in Christendom's largest church, the pope urged Catholics to follow the example of saints who he said struggled for justice so that "Easter gifts of harmony and peace may grow and flourish everywhere."

Leo, who is known for choosing his words carefully, has been ramping up his criticism of the Iran war in recent weeks.

The pope said last Sunday that God rejects the prayers of leaders who start wars and have "hands full of blood." He made a direct appeal to U.S. President Donald Trump on Tuesday, urging the president to find an "off-ramp" to end the war.

The pope will conclude his Easter celebrations on Sunday morning with a Mass in St. Peter's Square and will deliver a special blessing and message, which is usually a time when he makes a major international appeal.

-Reporting by Joshua McElwee in Vatican City; Editing by Matthew Lewis/Reuters