"With great regret," Pope Francis has accepted his doctors' advice to not travel to Dubai, United Arab Emirates, Dec. 1-3 and is looking at alternative ways the Vatican can participate in the U.N. Climate Change Conference, the director of the Vatican press office said.

The pope was scheduled to be among dozens of world leaders addressing the World Climate Action Summit at the beginning of the conference, commonly known as COP28.

"Although the Holy Father's general clinical condition has improved with regard to the flu and inflammation of the respiratory tract," for which he had been receiving treatment since Nov. 25, "doctors have asked the pope not to make his planned trip to Dubai," Matteo Bruni, director of the Vatican press office, said Nov. 28.

"Pope Francis accepted the doctors' request with great regret and the trip is therefore canceled," Bruni said, adding that the Vatican is studying ways the pope and the Holy See still can "be part of the discussions" about addressing the climate crisis.

Early Nov. 25 Pope Francis canceled his day's meetings because of "flu-like" symptoms, and that afternoon he went to Rome's Gemelli Isola Hospital for a CT scan of his lungs.

"The CT scan ruled out pneumonia, but showed pulmonary inflammation that was causing some respiratory difficulties," Bruni had said Nov. 27. "For more effective treatment, a needle cannula was placed for the infusion of intravenous antibiotic therapy."

The IV access was visible on the pope's right hand Nov. 26 as he sat next to an aide in the chapel of his residence for the midday recitation of the Angelus. Because he was still unwell the pope, who will celebrate his 87th birthday Dec. 17, led the recitation of the prayer from the chapel instead of his studio window overlooking St. Peter's Square.

Since then, Pope Francis has postponed some audiences with large groups while continuing some meetings. However, Nov. 28 he spent more than two hours with the bishops of Spain discussing a recent Vatican-ordered visitation of the country's seminaries.

Bruni said the pope still planned to hold his weekly general audience Nov. 29, which was scheduled to take place in the Vatican audience hall rather than in St. Peter's Square.

To coincide with the COP28 conference, Pope Francis wrote and released his exhortation "Laudate Deum" ("Praise God"), a follow-up to his 2015 encyclical "Laudato Si', On Care for Our Common Home."

In the new document, he wrote that he hoped COP28 would "represent a change of direction," showing that the global community is serious about stemming the effects of climate change.