Pope Francis has cancelled a visit to patients at a Rome hospital at the last minute because of what the Vatican called a "sudden indisposition".
But the pope, who has cancelled a number of engagements in recent weeks due to minor health problems, will still receive the Madagascan president and host a celebration of the feast day of Saint Peter and Saint Paul this weekend, the Vatican said.
"The engagements on the Holy Father's agenda for Saturday June 28 and Sunday June 29 are confirmed," the Vatican's chief spokesman Father Federico Lombardi said in a text message to reporters.
"There is no reason for concern over the health of the pope," Lombardi said.
The Holy See said earlier in the day that the 77-year-old Argentine pontiff would not make a planned visit to Rome's Gemelli hospital, where he had been due to visit patients and say Mass.
People had already gathered at the hospital to await the pope when the Vatican issued a statement saying Angelo Scola, Cardinal of Milan, would read the homily in his place.
The crowd applauded when Scola sent his best wishes to the pope, leader of the world's 1.2 billion Catholics.
"I am sure I act for the hearts and minds of us all when I send a warm embrace to Pope Francis. May he overcome this indisposition quickly," Scola said.
Earlier on Friday, the pope had celebrated his daily mass at Santa Marta in the Vatican, where he lives, and held a series of audiences. Italian media said the pope had cancelled the appointment because he was "very tired".
The pope, who suffers from sciatica, cancelled a scheduled walk in a procession through the streets of Rome last week, a decision the Vatican said was to conserve his strength for coming engagements.
He cancelled an engagement the week before due to a slight fever, but subsequently made a number of public appearances during which he seemed to be in good health.