VATICAN CITY — Pope Leo XIV called for a genuine and just peace in Ukraine and an immediate ceasefire in Gaza, in his first Sunday noon blessing as pontiff that featured some symbolic gestures suggesting a message of unity in a polarized Catholic Church.

“I, too, address the world’s great powers by repeating the ever-present call ‘never again war,’” Leo said from the loggia of St. Peter’s Basilica to an estimated 100,000 people below.

It was the first time that Leo had returned to the loggia since he first appeared to the world on Thursday evening following his remarkable election as pope, the first from the United States. Then, too, he delivered a message of peace.

Leo was picking up the papal tradition of offering a Sunday blessing at noon, but with some twists. Whereas his predecessors delivered the greeting from the studio window of the Apostolic Palace, off to the side of the piazza, Leo went to the very center of the square and the heart of the church.

Part of that was logistics: He didn’t have access to the papal apartments in the palace until later Sunday, when they were unsealed for the first time since Pope Francis’ death.

Leo also offered a novelty by singing the Regina Caeli prayer, a Latin prayer said during the Easter season which recent popes would usually just recite and harked back to the old Latin Mass of the past.

Leo quoted Pope Francis in denouncing the number of conflicts ravaging the globe today, saying it was a “third world war in pieces.”

“I carry in my heart the sufferings of the beloved Ukrainian people,” he said. “Let everything possible be done to achieve genuine, just and lasting peace as soon as possible.”

As a bishop in Chiclayo, Peru, at the start of Russia’s 2022 full-scale invasion of Ukraine, then-Bishop Robert Prevost had not minced words in assigning blame to Moscow. According to a clip of a TV interview on the Peruvian show “Weekly Expression,” circulating in Italian media Sunday, Prevost said it was an “imperialist invasion in which Russia wants to conquer territory for reasons of power given Ukraine’s strategic location.”

In his remarks Sunday, Leo also called for an immediate ceasefire in Gaza, and for humanitarian relief to be provided to the “exhausted civilian population and all hostages be freed.”

Leo also noted that Sunday was Mother’s Day in many countries and wished all mothers, “including those in heaven” a Happy Mother’s Day.

The crowd, filled with marching bands in town for a special Jubilee weekend, erupted in cheers and music as the bells of St. Peter’s Basilica tolled.

Angela Gentile of Bari arrived in the square three hours early to be in place. Nonplussed that cardinals had elected yet another non-Italian pope, she said she was happy Leo came to the central balcony of the basilica, so the crowd could see him face-to-face. “What’s good for the Holy Spirit works for me,” she said. “I have trust.”

More than 50 pilgrims from Houston, Texas, were in the square, too, waving three large American flags. They were in Rome on a pre-planned Holy Year pilgrimage and said they were proud to be part of this historic occasion.

The 69-year-old Chicago-born missionary was elected 267th pope on Thursday. He has a busy week of audiences before his formal installation Mass next Sunday.