Thousands of worshippers flocked to St Peter's Square on Sunday to hear Pope Leo XIV deliver his first Easter Mass address as pontiff.

Framed by white roses on the central balcony of the Vatican's basilica, the pope called on those who have the power to unleash wars to choose peace.

On this day of celebration, let us abandon every desire for conflict, domination and power, and implore the Lord to grant his peace to a world ravaged by wars, he said.

The first US-born pope has become a vocal critic of the Iran war, and has used recent public addresses to denounce global conflicts and urge de-escalation.

Pope Leo waved to the crowd gathered in the square below before delivering his Urbi et Orbi blessing - Latin for to the city and the world.

He highlighted the importance of Jesus' nonviolent example amid suffering, urging those with weapons to lay them down. While he did not name specific conflicts, he condemned the growing indifference to violence.

Amid vibrant spring decorations in St Peter's Square, Pope Leo concluded with blessings in multiple languages and announced a prayer vigil for peace scheduled on April 11.