Pope Leo XIV called for "no more war" in his first Sunday blessing and address in St. Peter's Square at the Vatican.

He urged peace in Ukraine, called for a ceasefire and the release of hostages in Gaza, and welcomed the truce between India and Pakistan.

The Chicago-born Pope, Robert Francis Prevost, was elected to head the Catholic Church on Thursday.

What did Pope Leo say?

Speaking from the balcony of St. Peter's Basilica, the new pontiff noted the recent 80th anniversary of the end of World War II, which killed some 60 million people and repeated the frequent call of the late Pope Francis, "No more war!"

Leo said today's world was living through "the dramatic scenario of a Third World War being fought piecemeal," repeating another phrase coined by Francis.

The new pope said he carries in his heart the "suffering of the beloved people of Ukraine," and appealed for negotiations to reach an "authentic, just and lasting peace."

He also called for an immediate ceasefire in the war in Gaza, saying it left him "profoundly saddened," urging the delivery of humanitarian aid and the release of the remaining hostages held by the militant group Hamas.

Speaking about the flare-up between India and Pakistan, Leo said he was glad to hear of the recent ceasefire and hoped negotiations would lead to a lasting accord between the nuclear-armed neighbors.

Crowds pack St. Peter's Square

The new pope was cheered loudly time and again by the 100,000 people gathered in the Vatican. 

St. Peter's Square was packed with pilgrims, well-wishers and the curious, many holding up flags from their homelands. Leo gave many special groups a mention.

Earlier Sunday, Leo celebrated a private Mass near the tomb of St. Peter, the apostle who is considered to be the first pope.

On Saturday, Leo prayed before the tomb of Pope Francis, located across town at the St. Mary Major Basilica.

The 69-year-old was elected 267th pope of the Catholic Church on Thursday following the April 21 death of Francis. The conclave to select him lasted merely some 24 hours.

Edited by: Louis Oelofse