Pope Benedict's successor needs to be a younger man, the Vicar-General of Rome Cardinal Agostino Vallini said on Friday.
Benedict's papacy ended on Thursday and cardinals have said they want to elect a new pontiff by Easter.
"I believe that the Church needs a pope with more youthful strength and vigour," Vallini said.
He said no one yet knew what intellectual role Benedict might have during his retirement in a monastery inside the Vatican.
"However, I believe we can't deny ourselves the wisdom of his great teachings which will be an increasingly important reference point in the future," Vallini said.
Angelo Sodano, dean of the College of Cardinals, Friday summoned the prelates to meet in general congregations starting Monday to discuss the problems facing the Church and set a date for the start of the secret election, or conclave, to elect Benedict's successor.
Benedict's surprise abdication at the age of 85 on grounds of age and failing physical and mental strength has been openly criticised by Australia's most senior Catholic, Cardinal George Pell, and by Poland's Cardinal Stanislaw Dziwisz.
Benedict's successor will be chosen by 115 cardinal-electors (those younger than 80 years) through ballot held in the Vatican's Sistine Chapel.
A two-thirds-plus-one vote majority is required. Sixty-seven of the electors were appointed by Benedict XVI, and the remainder by his predecessor John Paul II.
