Pope Leo XIV calls for end to wars in Ukraine, Gaza

Pope Leo already has events on his calendar for his first week as the head of the Catholic Church.

On Saturday, he will meet with the cardinals, and on Sunday will be a noon-time prayer from the Central Loggia of the Basilica.

On Monday, Leo will meet with the world press and on Friday is a meeting with the ambassadors of the Embassies to the Holy See.

Pope Leo will hold his inaugural Mass on Sunday, May 18.

Rome is prepared for both "very busy Sundays" for the pope's events this Sunday and on May 18, a spokesperson for Mayor Roberto Gualtieri said.

Both days will attract large crowds and therefore require "the same security put in place for Pope Francis' funeral," the spokesperson said.

-ABC News’ Phoebe Natanson and Camilla Alcini

Cardinal Maung Bo, the archbishop of Yangon, in Myanmar, told ABC News he hopes Pope Leo XIV will be able to "build a bridge" with President Donald Trump.

Bo said he is "very excited" for the first American pope and that Leo will be a "good shift" for the Catholic Church.

Bo would not reveal if he voted for Leo, formerly Cardinal Robert Prevost, during the conclave.

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Cardinal hopes Pope Leo will 'build a bridge' with TrumpCardinal Maung Bo, the archbishop of Yangon, told ABC News’ James Longman that he hopes Pope Leo XIV will be able to "build a bridge" with President Donald Trump.

ABCNews.com

John Prevost, one of the pope's older brothers, told "GMA" on Friday he was able to speak to his sibling yesterday for about 30 seconds and they were able to share a brief moment together where he was able to congratulate him.

"I think from the time he was 5 or 6 years old, he knew this was his fate," John Prevost told "GMA" early Friday morning. "Not that he would be a pope, but that he would be a priest. He knew that from a very young age. His idea never faltered all through grammar school, high school, college."

"I don't know if he was born with it or if it was a seed planted by our parents. He went that route, and I went catholic school teacher principal for my career. So somewhere the seed of faith was planted in us," Prevost continued.

He said that if their parents were still alive that they would be feeling "extreme joy" and "extreme pride" about their son but that they would also be concerned as to how he would handle his new role because "it's a heavy weight on his shoulders."

"I'm concerned," said Prevost. "It is quite a responsibility that he's going to face now because he's got the task of trying to bring the world's Catholics together. I think we're splitting apart quickly. Maybe he can do something to bring it back. People are leaving the church. There are factions in the church. ... I think he's got to face those things and somehow talk about it and bring people together to talk about it, to get world-wide opinion."

Rev. John Wauck has told ABC News that the pope views America and the West as “missionary territory” after listening to Pope Leo's homily from the Sistine Chapel on Friday morning.

“Even today, there are many settings in which the Christian faith is considered absurd, meant for the weak and unintelligent. Settings where other securities are preferred, like technology, money, success, power, or pleasure," the newly elected pope said. “These are contexts where it is not easy to preach the Gospel and bear witness to its truth, where believers are mocked, opposed, despised or at best tolerated and pitied."

"Yet, precisely for this reason, they are the places where our missionary outreach is desperately needed. A lack of faith is often tragically accompanied by the loss of meaning in life, the neglect of mercy, appalling violations of human dignity, the crisis of the family and so many other wounds that afflict our society," the pope continued. “Today, too, there are many settings in which Jesus, although appreciated as a man, is reduced to a kind of charismatic leader or superman. This is true not only among non-believers but also among many baptized Christians, who thus end up living, at this level, in a state of practical atheism."