Pope Francis in NYC: Pontiff heads to UN, Ground Zero (PHOTOS, VIDEOS)

The pontiff took to the pulpit on the world stage Friday morning with a formal address to the UNGA. The 193-member international organization is celebrating the 70th anniversary of its founding in 2015. Francis is the fourth pope to speak to the general assembly.

Before addressing world leaders, he talked to about 400 UN staffers in the Secretariat lobby, thanking them for making “possible many of the diplomatic, cultural, economic and political initiatives” of the United Nations.

Pope Francis laid a wreath at a memorial to UN staff who have lost their lives around the world while doing their jobs.

He also blessed the children in attendance.

During his speech to the UNGA, Pope Francis took on many hot-button international issues, calling on the world to quickly address climate change and help the least fortunate members of society.

“Economic and social exclusion is a complete denial of human fraternity and a grave offense against human rights and the environment,” Francis said, adding that “the poorest are those who suffer most from such offenses” because “they are cast off by society, forced to live off what is discarded and suffer unjustly from the abuse of the environment.”

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“Any harm done to the environment,” he said, “is harm done to humanity.”

He also called on the UNGA to address the humanitarian crisis overtaking Europe as migrants and refugees flood out of the Middle East.

Pope Francis then left the United Nations and headed to the World Trade Center complex, where he was joined by some 1,000 members of the 9/11 community at the National September 11 Memorial & Museum.

After a moment of silence in front of one of the twin memorial pools, which sits within the footprint left by the southern Twin Tower, the pope laid a white rose on the bronze panel surrounding the fountain. The names of every person who died in the 2001 and 1993 terrorist attacks on the World Trade Center are inscribed on the panel.

Once inside the National September 11 Museum, the pontiff met with local representatives of the world religions and held an interfaith meeting for peace.

“The name of so many loved ones are written around the towers’ footprints. We can see them, we can touch them, and we can never forget them,” Francis said in his address, which he gave in Spanish, during the service. “This place of death became a place of life too, a place of saved lives, a hymn to the triumph of life over the prophets of destruction and death, to goodness over evil, to reconciliation and unity over hatred and division.”

Rabbi Elliot Cosgrove of the Park Avenue Synagogue in Manhattan and Imam Khalid Latif, executive director and chaplain of the Islamic Center at New York University, also spoke during the meeting.

Pope Francis then met with relatives of those who died in the 9/11 terrorist attacks. Former New York Mayor Michael Bloomberg, the chairman of the National September 11 Memorial & Museum, introduced the family members to the pontiff.