Roman Catholic cardinals will meet in a secret conclave to elect the new leader of the global church starting from May 7, a senior Vatican source said on Monday.
Some 135 cardinals, all under the age of 80 and from across the world, are eligible to take part in the conclave and decide who should be the next leader of the 1.4-billion-member church.
The previous two conclaves, held in 2005 and 2013, lasted just two days.
The 16th-century Sistine Chapel, where conclaves are held, was closed to tourists on Monday to allow for preparations for the vote.
The past two conclaves, in 2005 and 2013, lasted just two days. But Swedish Cardinal Anders Arborelius said on Monday he expects this conclave may take longer, as many of the cardinals appointed by Francis have never met each other before.
Francis made a priority of appointing cardinals from places that had never had them, such as Myanmar, Haiti and Rwanda.
