Also Monday, Britain's top cardinal, Keith O'Brien, resigned and decided not to participate in the upcoming papal election following published reports in a British newspaper that he made unwanted sexual advances toward four priests in Scotland in the 1980s.
He has denied the allegations.
The Scottish cardinal, 74, is the latest voting member of the College of Cardinals to be tainted by scandal.
U.S. Cardinal Roger Mahony has also faced pressure to bow out of the conclave on the grounds that their moral authority has been compromised because of the church sex-abuse scandal. Church documents show that for more than a decade he enabled priests to keep molesting children rather than report them to law enforcement.
Documents from the Archdiocese of Los Angeles show that Mahoney covered up for pedophile priests.
Mahony is already in Rome and has been blogging about the upcoming conclave and lashing out at his critics for persecuting him.
Pope Benedict issued new rules about the timing and procedures of the vote to choose his successor.
Benedict has already given the College of Cardinals the go-ahead to move up the start date of the conclave, tossing out the traditional 15-day waiting period. But the cardinals won't be able to set a date until their official meetings begin Monday.
The Associated Press contributed to this report.