The pope, who is breathing through a tube in his throat, was fitted with the feeding tube after widespread reports that he has been having difficulty swallowing food.

The announcement came two hours after the pope made another brief appearance at the window of his apartment, during which he struggled, but failed, to speak to pilgrims gathered in St. Peter’s Square for his regular weekly audience.

Just as he did Easter Sunday, the pope tried to speak, but all he managed were a few rasping grunts before a hand pulled his microphone away. He also appeared to have difficulty controlling his movements - his head lolled and his neck twitched.

But he managed to make the sign of the cross to bless the crowd, while a bishop read the customary greeting in several languages.

The Vatican didn’t say when the tube was inserted, but there was no sign of it during his four-minute appearance at the study window. Medical experts said a nasal feeding tube, which would typically remain in place between meals, would have been visible had it been present.

This latest twist to the saga of the 84-year-old pope’s health problems brought closer the possibility that the Vatican may one day have to grapple with the dilemmas posed by a permanently incapacitated pontiff.

Although the Vatican said the pope spoke before he left the hospital March 13, he has not spoken publicly since.