Archbishop Bernardito Auza, head of the Holy See's permanent observer mission at the United Nations, told Vatican Radio: "There is so much interest. Everybody wants to see the Pope, even from a distance. The dream of so many is to have a selfie with the Pope."

Pope Francis is scheduled to address the UN General Assembly Sept. 25.

Auza told the radio Aug. 13 that the release in June of Pope Francis' encyclical, Laudato Si', increased interest in the Pope's visit and increased the number of requests he has received for tickets to see the Pope. His office has distributed hundreds, if not thousands, of copies of the document, he said.

The UN delegations of developing countries in particular, he said, "see the Pope as a kind of flag bearer, somebody who expresses their aspirations and positions."

The encyclical and its plea for strong international action to slow climate change have been a constant topic of discussion at UN gatherings, and not just in private conversations, the archbishop said.

In public and in private, he said, people "cite passages from the encyclical, which is an indication not only that they have talked about it, but that many have read it and have enjoyed reading it."

The Pope's call in the encyclical and in his speeches for an economic model that does not think only of "immediate profit without thinking what it does to the environment or what it does to the poor," he said, "really strikes a chord among most of the delegations."

Auza is hopeful that the encyclical and the inspiration it is providing will help national delegations rally the political will to reach an agreement for strong measures to counter climate change when they meet in Paris in November and December for the UN Climate Change Conference.

"The encyclical has been used at every turn in order to argue for a significant accord during the Paris conference," he told Vatican Radio.

The encyclical has given delegates "inspiration, philosophy, theology — we might say moral arguments — on why we should do this," he said. "I'm sure that the encyclical has already influenced a lot the minds and dispositions of many delegations, many countries.

"Of course, I have talked to some delegations who say, 'Yes, we really love this line of thinking of the Pope, of listening to the Pope, but we also have our technical problems," he said. But he is still hopeful that the Pope will be persuasive.