Ancient bones said to belong to St Nicholas, the fourth-century saint who inspired the legend of Santa Claus, may indeed be from the Father Christmas himself, Oxford scientists have found.

The remains of St Nicholas, one of the most revered Orthodox Christian saints, have been held in the Basilica di San Nicola church in Bari, Italy since 1087 AD.

Over the years relic fragments have been acquired by various churches around the world, calling into question how the bones can all be from the same person.

Using a micro-sample of bone fragment, Professor Tom Higham and Georges Kazan, from Oxford University in the UK, have for the first time tested one of these bones.

The radio carbon dating results pinpoint the relic's age to the fourth century AD - the time that some historians believe that St Nicholas died (around 343 AD).

The results suggest that the bones could in principle be authentic and belong to the saint, researchers said.

"Many relics that we study turn out to date to a period somewhat later than the historic attestation would suggest," said Higham.

"This bone fragment, in contrast, suggests that we could possibly be looking at remains from St Nicholas himself," he said.

St Nicholas is thought to have lived in Myra, Asia Minor, which is now modern day Turkey.

According to legend, he was a wealthy man who was widely known for his generosity, a trait that inspired the legend of Father Christmas as a bringer of gifts on Christmas Day.

Believed to have been persecuted by the Emperor Diocletian, the saint died in Myra, where his remains became a focus of Christian devotion.

His remains are said to have been taken away by a group of Italian merchants and transported to Bari, where the bulk of them sit to this day in the Basilica di San Nicola.

The bone analysed is owned by Father Dennis O'Neill, of St Martha of Bethany Church, Shrine of All Saints in Morton Grove Illinois, US, the researchers said.