(CNN) — ROME (CNN) -- The Catholic cardinals gathered in Rome and will vote later Friday on the date for the secret election, or conclave, to elect a new pope, a Vatican spokesman said.
The conclave is not expected to begin before Monday but could start some time next week, said the Rev. Federico Lombardi.
There will be 115 cardinal-electors taking part in the conclave, the Vatican confirmed. Only those younger than 80 are eligible to vote.
The cardinals voted Friday morning to accept the letters of explanation of two cardinal-electors who are eligible to vote for the next pope but will not attend the conclave: Keith O'Brien of Scotland and Julius Riyadi Darmaatmadja of Indonesia.
Darmaatmadja cited health reasons, and O'Brien cited personal reasons.
O'Brien resigned in scandal last week after allegations that he made sexual advances toward young men studying to be priests. He apologized in a statement Sunday, saying, "There have been times that my sexual conduct has fallen below the standards expected of me as a priest, archbishop and cardinal."
Since Monday, the cardinals have been uniting for what are known as General Congregations, a series of meetings in which they discuss the issues facing the church.
These include how to tackle the issue of child sex abuse by priests and a scandal over leaks from the Vatican last year that revealed claims of corruption within the Roman Catholic Church hierarchy.
There is no rule about how long has to elapse before a conclave begins, Lombardi said.
In 2005, it was three days after the end of the General Congregations, he said, but that's not necessarily a guide for this year.