Pope Francis is expected to be discharged on Saturday from the Rome hospital where he is being treated for bronchitis as his recovery proceeds "in a “normal” way, even had pizza for dinner and will be in St. Peter's Square for Palm Sunday Mass, the Vatican said.

Vatican spokesman Matteo Bruni gave the update in a written statement on Friday.

In a subsequent statement, Bruni said that Francis was due to be in the square for the Mass, which marks the start of Holy Week and ushers in a series of solemn public ceremonies that culminate on Easter on April 9.

Francis, 86, was hospitalised on Wednesday at Gemelli Polyclinic, where doctors said the pontiff was receiving antibiotics intravenously to treat his bronchitis.

“Yesterday went well, with a normal clinical recovery,″ Bruni said.

“In the evening (of Thursday), Pope Francis had dinner, eating a pizza, together with all those who are assisting him in these days of the hospital stay,” the spokesman said, including doctors, nurses, assistants and Vatican security personnel.

On Friday morning, the pope read newspapers and resumed his work after breakfast.

The pontiff's return to the Vatican hotel where he lives “is expected for tomorrow, as a result of the last tests of this morning,″ Bruni said.

The spokesman later added that, given the pope would return to the Vatican on Saturday, Francis was expected to be present in the square for Palm Sunday Mass. He didn't indicate whether Francis would deliver a homily during the ceremony, a particularly long service, or if someone else might read it for him.

Medical staff decided to hospitalise him on Wednesday after he returned to his Vatican residence following his customary weekly public audience in St. Peter's Square. The Vatican reported he had experienced difficult breathing in the previous days.