Pope Francis shakes hands with Alitalia's flight attendant as he boards a plane for his pastoral trip to Egypt at the Leonardo da Vinci-Fiumicino Airport in Rome, Italy, April 28, 2017 Reuters

Pope Francis waves as he leaves for his pastoral trip to Egypt at the Leonardo da Vinci-Fiumicino Airport in Rome, Italy, April 28, 2017 Reuters

Pope Francis arrives at Cairo's airport, Egypt, Friday, April 28, 2017 AP

Pope Francis leaves Cairo's International Airport upon his arrival in the Egyptian capital on April 28, 2017 AFP

Pope Francis (L) is greeted by officials upon his arrival at Cairo's International Airport on April 28, 2017 AFP

Pope Francis, in the car, is escorted by security forces as he leaves Cairo's airport, Egypt, Friday, April 28, 2017 AP

Pope Francis waves from the window of his car as he leaves Cairo's airport, Egypt, Friday, April 28, 2017 AP

Pope Francis (C-R) walks alongside Muslim clerics during a visit at the prestigious Sunni institution Al-Azhar in Cairo on April 28, 2017 AFP

Pope Francis (C) is greeted by Muslim clerics during a visit at the prestigious Sunni institution Al-Azhar in Cairo on April 28, 2017 AFP

Pope Francis leaves Cairo's International Airport upon his arrival in the Egyptian capital

Egyptian President Abdel Fattah al-Sisi meets Pope Francis upon his arrival to Cairo,

Egyptian President Abdel Fattah al-Sisi (R) greeting Pope Francis upon the latter's arrival at the presidential palace in Cairo during an official visit to Egypt.