The Vatican will bar priests, religious and lay faithful participating in the annual Ad Petri Sedem pilgrimage from entering St. Peter’s Basilica on Saturday, Oct. 24, extending restrictions beyond the celebration of the traditional Latin Mass to the pilgrims’ customary gathering for prayer at the tomb of St. Peter.

According to the organizers, the decision was communicated in recent days in a letter from the Vatican Secretariat of State. "Your procession is not allowed to enter into St. Peter's Basilica," the letter stated, according to Christian Marquant, the pilgrimage's chief organizer.

Speaking on Friday afternoon at the conclusion of a conference at the Augustinianum, Marquant, President of Paix Liturgique, announced the Secretariat of State’s decision to participants. "We will not enter into St. Peter’s tomorrow," he said, adding that accusations had been made that last year’s Mass was "instrumentalized."

The decision follows an earlier refusal to authorize the celebration of the traditional Latin Mass inside the Vatican Basilica. The latest restriction goes further, preventing pilgrims from entering as a group to pray before the tomb of the Apostle Peter.

Established in 2012, the annual Ad Petri Sedem pilgrimage — also known as the Summorum Pontificum pilgrimage — brings together priests, religious and lay faithful from around the world to deepen their faith, express their attachment to the traditional Roman liturgy and affirm their communion with the Successor of St. Peter.

The pilgrimage is organized by the Coetus Internationalis Summorum Pontificum (CISP), an international coalition of associations devoted to the traditional liturgy. It takes its name from Pope Benedict XVI’s 2007 motu proprio Summorum Pontificum, which liberalized the celebration of Mass according to the 1962 Roman Missal.

Last year, Pope Leo XIV authorized Cardinal Raymond Leo Burke to celebrate a traditional Pontifical Mass in St. Peter's Basilica on Oct. 25, 2025, at the Altar of the Chair. The celebration was a major moment for the pilgrimage, making this year's exclusion from the basilica a striking contrast with the events of 2025.