Pontiff calls for peace and unity at the service, which attracts dignitaries from around the world.
Pope Leo XIV has met Ukrainian President Volodymyr Zelenskyy after his inaugural Mass in the Vatican, where he delivered a message of love and unity to a crowd of 200,000 pilgrims.
“We thank the Vatican for its willingness to serve as a platform for direct negotiations between Ukraine and Russia. We are ready for dialogue in any format for the sake of tangible results. We appreciate the support for Ukraine and the clear voice in defense of a just and lasting peace,” Zelenskyy posted on X.
No statement has been issued by the Vatican yet regarding Sunday’s meeting.
Leo, formerly Cardinal Robert Prevost, was officially installed as the head of the Catholic Church at an outdoor Mass in St Peter’s Square with world leaders and European royalty in attendance.
In his sermon, Leo, the first American pope, called for unity within the church, saying he wanted it to act as a force for peace in the world.
“I would like that our first great desire be for a united church, a sign of unity and communion, which becomes a leaven for a reconciled world,” he said.
“In this our time, we still see too much discord, too many wounds caused by hatred, violence, prejudice, the fear of difference and an economic paradigm that exploits the Earth’s resources and marginalises the poorest.”
Leo said he was assuming the role as leader of the world’s 1.4 billion Roman Catholics “with fear and trembling” and insisted he would not lead like “an autocrat”.
“It is never a question of capturing others by force, by religious propaganda or by means of power. Instead, it is always and only a question of loving, as Jesus did,” he said, in an apparent nod to the split between conservative and liberal factions within the church.
‘The rich heritage of the Christian faith’
The 69-year-old pope, who was born in Chicago and spent years as a missionary in Peru, succeeds the late Pope Francis, whose 12-year tenure was marked by tensions with traditionalists within the church. In an apparent nod to conservatives, Leo said he was committed to protecting “the rich heritage of the Christian faith” and repeatedly used the words “unity” and “harmony”.
Before the ceremony, Leo took his first popemobile ride through St Peter’s Square, waving to crowds cheering, “Viva il Papa.”
Dignitaries in attendance included the presidents of Israel, Peru and Nigeria; the prime ministers of Italy, Canada and Australia; German Chancellor Friedrich Merz; and Spain’s King Felipe and Queen Letizia.
The United States delegation was led by Vice President JD Vance, a Catholic who had clashed with Francis over the White House’s approach to immigration. Vance shook hands with Zelenskyy at the start of the ceremony, in contrast to the previous meeting between the two men and President Donald Trump in a fiery encounter in front of the world’s media at the White House in February.
Leo prayed for the victims of the conflicts in Ukraine and Gaza in his sermon, saying Ukraine was being “martyred” and lamenting that Palestinians were being “reduced to starvation”.