Secretary-General Ban Ki-moon said the timing was no coincidence, pointing to Pope Francis' past statements on the key issues facing the world.
"Across the global agenda, his holiness is a resounding voice of conscience," Ban said.
The pope, in New York as part of his first visit to the United States, said all mankind has a right to the environment but “is not authorized to abuse it, much less to destroy it.”
And he urged more international intervention to stop the suffering of those at the center of conflicts in the Middle East and Africa, who he said face the choice of either “fleeing or of paying for their adhesion to good and to peace by their own lives, or by enslavement.”
The pontiff continued, "In wars and conflicts, there are individual persons, our brothers and sisters, men and women, young and old, boys and girls who weep, suffer, and die. Human beings who are easily discarded when our only response is to draw up lists of problems, strategies, and disagreements.”
He cited an "urgent need to work for a world free of nuclear weapons." And he called for the world's leaders to provide its people with the "minimum spiritual and material needs to live in dignity" and access to education, including for "girls who are excluded in certain places."
Melinda Gates, co-founder of the Gates Foundation, praised the pope's commitment to eradicating poverty and to securing girls' right to education worldwide.
"Having Pope Francis as a champion in the fight against extreme poverty is a boost for women and children everywhere. As a Catholic, I’m proud to stand with Pope Francis as he calls for an end to poverty and for recognizing the fundamental dignity of women and girls," Gates wrote in an email.