Story highlights "This is the most important decision that some of us will ever make," says U.S. cardinal

Not all cardinal-electors have to be present for the conclave date to be set

110 of the 115 cardinal-electors have now arrived in Rome, says Vatican spokesman

The Sistine Chapel closes to the public for preparations ahead of the conclave

Catholic cardinals have met for a second day Tuesday at the Vatican, but have not yet set a timetable for selecting a new pope

A total of 110 out of the 115 cardinal-electors, those younger than 80 who are eligible to elect the pope, are now in Rome, Vatican spokesman the Rev. Federico Lombardi said Tuesday.

The five cardinal-electors who have not yet arrived have been in touch with the College of Cardinals, and the Vatican knows when they are coming, he said. He did not say when that would be, however, or give reasons for their delayed arrival.

No date has yet been proposed for the conclave to select Pope Benedict XVI 's successor, said Lombardi.

It is not necessary for all the cardinal-electors to be present for the conclave date to be set, he said, but they do have to be given time to get there.

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Another Vatican spokesman, the Rev. Thomas Rosica, said: "There is no desire to rush things but to take this time for discernment and reflection, and that's been evident in the meetings thus far."

The famous Sistine Chapel, where the secretive conclave takes place, was closed to the public at lunchtime Tuesday for preparations and will remain so until further notice, the official Vatican Museums website said.

Those cardinals already in Rome met twice Monday, in the morning and in the evening, as they began a series of meetings known as general congregations.

The group decided that congregations on Tuesday and Wednesday would take place in the morning only.

The general congregations are a key step before the conclave.

Cardinals who want to speak in the meetings sign up to do so, and can speak for as long as they want on any topic they want, Lombardi said.

So far, 33 cardinals have spoken. There are 148 in the congregations as of Tuesday morning, he said.

According to Italian media reports, discussions Monday focused on an internal investigation into leaks from the Vatican, the outcome of which has so far been seen only by Benedict, and the church's handling of the scandal over child sex abuse by priests.

The cardinals also talked about the kind of pope they want to see at the head of the world's 1.2 billion Roman Catholics.

'As long as it takes'

U.S. Cardinals Sean O'Malley of Boston and Daniel DiNardo of Galveston-Houston, speaking to reporters after Tuesday's congregation, said the cardinals were in no hurry to set a date for the conclave.

"I think this is the most important decision that some of us will ever make, and we need to give it the time that's necessary," O'Malley said. "We want to have enough time in the general congregations so that when we go into the conclave, it's a time of decision. This is a time of discernment and prayer and reflections."

"It takes as long as it takes," DiNardo said, adding that there were "plenty of points of view among the cardinals" about when the conclave should begin.

"No one really wants to rush this if it can't be rushed," he said.

Both laughed off speculation that they could be elected pope, although some betting agencies rate O'Malley as the most likely American to become pope.

O'Malley was asked if he would continue to wear his brown Capuchin robe if he did become pontiff.

"I have worn this uniform for 40 years and I expect to wear it until I die, and that's because I don't expect to be elected pope," he said.

DiNardo, who lives in Texas, was then asked if he would keep wearing a cowboy hat if he became pope. "That's an 'Alice in Wonderland' question. We're going down the rabbit hole in terms of my being elected pope," he said.

Transfer of power

Benedict announced his intention to step down on February 11 and resigned Thursday, becoming the first pope to do so in almost 600 years. The transfer of papal power has almost always happened after the sitting pope has died.

Normally, the College of Cardinals is not allowed to select a new pontiff until 15 to 20 days after the office becomes vacant. However, Benedict amended the 500-year-old policy to get a successor into place more rapidly.

The cardinals may to be able to do so before March 15, Lombardi has said.

This would give the new pontiff more than a week to prepare for the March 24 Palm Sunday celebrations.

Some gambling houses are offering odds on who will next lead the Catholic Church.

Favorites include the archbishop of Milan, Italy, Cardinal Angelo Scola; Cardinal Tarcisio Bertone of Italy; Cardinal Peter Turkson of Ghana, who would become the first African pontiff since Pope Gelasius I died more than 1,500 years ago; and Cardinal Marc Ouellet of Canada, who would become the first North American pope.

While Benedict has no direct involvement in the selection of his successor, his influence will be felt: He appointed 67 of at least 115 cardinals set to make the decision.

Wounded 'hearts and minds'

One former cardinal who won't participate in the conclave is Keith O'Brien of Scotland, who resigned last month. O'Brien apologized Sunday for sexual impropriety, without specifying any incident.

"To those I have offended, I apologize and ask forgiveness," he said in a statement.

The Vatican refused to answer questions Monday about whether it would discipline O'Brien.

But others did comment.

"It looks as if the incidence of abuse is practically zero right now as far as we can tell, but they are still the victims, and the wound therefore is deep in their hearts and minds very often," Cardinal Francis George, archbishop of Chicago, told reporters in Rome. "As long as it's with them, it's with all of us. And that will last for a long time, so the next pope has to be aware of this."

Philip Tartaglia, the archbishop of Glasgow and apostolic administrator of the Archdiocese of St. Andrews and Edinburgh, will administer O'Brien's archdiocese until a new appointment is made.

"The most stinging charge which has been leveled against us in this matter is hypocrisy, and for obvious reasons," Tartaglia said Monday night in a sermon at St. Andrew's Cathedral in Glasgow. "I think there is little doubt that the credibility and moral authority of the Catholic Church in Scotland has been dealt a serious blow, and we will need to come to terms with that."

Representatives of a support group for abuse victims, Survivors Network of those Abused by Priests, or SNAP, called Monday for the cardinals to elect a new pope who is not a Vatican insider.

The group also called for some of the older cardinals to absent themselves from the General Congregations, arguing that some have been accused of complicity in protecting priests accused of sexually abusing children.

"Their peers should push them to stay home, or they should do so voluntarily, the group feels, for the sake of the church and to avoid heaping more pain on wounded victims and betrayed Catholics," a statement on SNAP's website said.

One of Italy's anti-clerical abuse networks, L'Abuso, petitioned senior Vatican Cardinal Tarcisio Bertone on Monday not to allow the participation in the conclave of an Italian cardinal it alleges helped protect priests who molested minors in the past.

Cardinals must vote in person, via paper ballot. Once the process begins, the cardinals aren't allowed to talk with anyone outside of the conclave. They cannot leave until white smoke emerges from the Vatican chimney -- the signal that a new leader has been picked.

More than 5,000 journalists are now accredited for the papal conclave, Lombardi said Tuesday. They cover 24 languages, he said.