The Vatican hinted Wednesday that Pope Benedict XVI could issue a letter in the week left in his pontificate that may speed the election of his successor.

The Vatican spokesman, the Rev. Federico Lombardi, said the pope -- the only person with the power to change canon law by fiat -- might send out a papal letter before his resignation takes effect Feb. 28, USA Today reported.

The letter would be a "Motu Proprio," a personal document that has the force of church law and addresses a specific need, Reuters reports.

Lombardi did not know if Benedict would shift the law setting the date for the conclave, but said his letter might offer "clarifications" on an unnamed subject.

Many experts have said the rules governing papal elections demand a conclave 15 to 20 days after the throne of St. Peter is vacant. Under those rules, March 15 is the earliest possible start. But canon law was designed to deal with the death of a pope and give the cardinal electors time to reach Rome for a funeral and then gather in the Sistine Chapel for the secret voting.

Since Benedict plans a farewell meeting with the cardinals on Feb. 28 before he flies off by helicopter to rest in private at Castel Gandolfo, the papal retreat, they will all be in Rome already.

There's no need to wait 15 days, Ambrogio Piazzoni, the vice prefect of the Vatican library, told the Associated Press as he parsed the language of the law. "The phrase 'must wait' doesn't say that you can't start before 15 days."

There is pressure to get a new pope in place before Palm Sunday, March 24. But the timing is also complicated by the solemnity of Lent, which frowns on celebrations such as the installation of a new pope. The only day that could be an exception is March 19, the Feast of St. Joseph. But electors would need to get into the conclave, and pick the next pope in time, USA Today notes.

On the other hand, some in the church object that an early conclave would give an unfair advantage to cardinals already in Rome and working in the Curia, the Vatican's central administration.

A short period before a conclave helps the curial cardinals in Rome operating on their home turf," Father Tom Reese, senior fellow at the Woodstock Theological Center at Georgetown University and author of several books on the Vatican, told Reuters.

"The curial cardinals are the ones that cardinals from outside Rome turn to for opinions about the other cardinals. The longer the pre-conclave period, the more time non-curial cardinals have to talk to each other and to get to know each other. The longer the period prior to the conclave, the less dependent outside cardinals are on the curial cardinals."

The Vatican has said Benedict will not participate in the conclave to elect his successor. He has said he plans to spend some time at Castel Gandolfo, his summer residence, before eventually moving into a convent in Vatican City.