Cardinals will gather for the papal conclave — the centuries-old tradition through which a new head of the Catholic Church is elected — starting on May 7, Vatican spokesperson Matteo Bruni said Monday.

The announcement comes after Pope Francis was laid to rest Saturday in a ceremony that saw world leaders and hundreds of thousands of mourners descend upon the Vatican to pay their respects.

Francis died one week ago on April 21, Easter Monday, at the age of 88. The pontiff’s death came after a protracted health battle that hospitalized him for weeks.

The Vatican announced the conclave’s start date following a fifth congregation of cardinals early Monday, which Bruni said was attended by more than 180 cardinals. A little over 100 of those cardinals will be electors in the forthcoming conclave, due to those over the age of 80 not being allowed to vote.

Bruni said that several cardinals spoke during the congregation, on issues including the Church and its relationship with the world — and how a new pope would need to be able to navigate the challenges that lie ahead.

Funeral rites for the late pope are expected to be held for nine days following his burial.

It is customary for the conclave to be held 15 to 20 days after the pope’s death, but until now the Holy See had not released the details of the gathering. Bruni said the conclave would not be held before May 7 due to the time required to make the necessary preparations.

The “conclave,” which stems from the Latin term for “with key,” is a church tradition that began in 1268 with a papal election that lasted almost three years and ended only when local residents of the central Italian city of Viterbo locked up the cardinals until a new pope was chosen.

Since then, it has become a significantly less chaotic process, with both Francis and his predecessor Pope Benedict XVI, elected within around two days.

This is a developing story. Please check back for updates.