The dean of the College of Cardinals, Cardinal Giovanni Battista Re, sent a letter to all cardinals — electors and non — on Monday, summoning them to the general congregation, which will begin on Tuesday at 9 a.m. local time. The general congregation will take place in the Synod Hall inside Vatican City.

A new pope will be selected to lead the Catholic Church following the death of Pope Francis. The pope is chosen during a highly secretive election called a conclave. Francis, 88, died on April 21. The pope will be honored with a nine-day mourning period known as the Novendiale, a tradition that began in Ancient Rome.