It would be the first time a pope has attended a United Nations climate change conference since its inception in 1995.

Francis wants to go to Dubai, Cardinal Pietro Parolin, the Vatican’s secretary of state, told Reuters on the sidelines of a Catholic-Jewish event in Rome yesterday, adding that no final decision had been taken.

Other Vatican sources put the probability that the pope would go to the Nov 30-Dec 12 event as high as 90%.

Heads of state usually attend only the opening sessions of the conferences and make keynote addresses. US president Joe Biden spoke at the start of the last two meetings in Sharm El-Sheikh, Egypt, last year and Glasgow, Scotland in 2021. Such conferences are also occasions for bilateral meetings.

Francis, 86, has made protection of the environment one of the hallmarks of his papacy and met last week with COP28 president Sultan Ahmed Al-Jaber.

In a major document on Oct 4, Francis appealed to climate change deniers and foot-dragging politicians to have a change of heart, saying they cannot gloss over human causes or deride science while the planet “may be nearing the breaking point”.

The document, known as an Apostolic Exhortation and titled Laudate Deum (Praise God), was a follow-up to Francis’ 2015 encyclical on the environment “Laudato Si” (Praise Be).

It was prompted by recent extreme weather events and mentioned the challenges facing COP28 several times.

Failure in Dubai, Francis said in the document, “will be a great disappointment and jeopardise whatever good has been achieved thus far”.

Francis uses a cane and wheelchair because of a knee ailment but his mobility issues have not prevented him from keeping a full schedule. In September, he made a trip to Mongolia and the French city of Marseille.