An archaeologist has sparked a Da Vinci Code-style hunt for the Holy Grail after claiming ancient records show it is buried under a 6th century church in Rome.

The cup - said to have been used by Christ at the Last Supper - is the focus of countless legends and has been sought for centuries.

Alfredo Barbagallo, an Italian archaeologist, claims that it is buried in a chapel-like room underneath the Basilica of San Lorenzo Fuori le Mura, one of the seven churches which Christian pilgrims used to visit when they came to Rome.

Mr Barbagallo based his claim on two years spent studying mediaeval iconography inside the basilica and a description of a particular chamber, in a guide to the catacombs written in 1938 by a Capuchin friar named Giuseppe Da Bra.

The friar describes a room of about 20 square metres with a vaulted roof ceiling. "In the corner of a wall-seat there can be seen a terracotta funnel whose lower part opens out over the face of a skeleton," he wrote.

Da Bra then explains that giving liquid refreshment (refrigerium) to the dead was part of ancient funeral rites.

According to Mr Barbagallo, who heads an association called Arte e Mistero [Art and Mystery], this funnel is the Grail...