VATICAN CITY - Pope Francis on Thursday said he was suffering from a highly infectious and acute form of bronchitis that has prevented him from making the trip to Dubai this weekend for the COP28 climate summit.

Francis, who turns 87 in December, has had a number of health problems in recent years that involved hospital stays, most recently in June. Despite his latest ailment, he is still working and meeting people.

"As you can see, I am still alive," he said in off-the-cuff remarks during an audience at a seminary on health and ethics, according to a Vatican transcript.

"The doctor didn't let me go to Dubai. The reason is that it is very hot there, and you go from heat to air conditioning, and (it's not convenient) in this bronchial situation. Thank God it wasn't pneumonia. It is a very acute, infectious bronchitis," he said.

Francis said he had no fever but was on antibiotics, confirming what the Vatican said in a statement on Wednesday.

During another audience on Thursday with theologians, the pope said: "Pray for me. Pray for me, not against, because this job is not easy. Thank you."

Cardinal Secretary of State Pietro Parolin told reporters on Wednesday he expected to lead the Vatican's delegation at the climate talks in Dubai.

(Reporting by Alvise Armellini; Editing by Janet Lawrence)