The Vatican also announced St Peter's, the world's largest church and the centre of global Catholicism, was getting a new app and digital booking system as it gears up for the anniversary on November 18.

"The entire terrace of the basilica will be accessible," compared with only one third of it today, Cardinal Mauro Gambetti, the Archpriest of the basilica, told a press conference.

A current "refreshment area" will be approximately doubled to around 100 square metres, he said.

The Vatican had previously sought to play down reports of a cafe on the terrace, which had sparked anger about the potential commercialisation of a sacred place.

Exhibitions will also be staged on the terrace, including for children, relating to the building's history, construction and maintenance.

Some 20,000 people a day visit the basilica, a jewel of Renaissance architecture, and managing the numbers is a major challenge.

The Vatican announced on Monday a new real-time booking system for access to the basilica, fuelled by a network of sensors that monitor how many people are inside.

And it launched a new app for liturgies in the Basilica, which will allow pilgrims to follow mass by Pope Leo XIV in 60 languages via their smartphones.

The basilica -- located in Vatican City, the world's smallest state -- contains the tomb of St Peter, one of the 12 disciples of Jesus Christ and the first pope.

The first stone for the basilica, which replaced an older one on the site, was laid by Pope Julius II in 1506, and it was completed in 1626.