Baseball hat Benedict: Pope sports a very casual cap

The 83-year-old even colour-coordinated his new cap, perhaps mindful of the need for it to blend in with his white robe and white hair.

Pope Benedict donned the trendy hat as he walked around his estate in Castel Gandolfo, south of Rome.

The cap also served the more useful purpose of keeping the hot summer sun off the Pope's head.

The move isn't the first time that the Vatican has broken with tradition this week.

It emerged at the weekend that officials have decided not to fly the Pope home to Italy on British Airways at the end of his state visit to the UK this autumn.

The decision is due, in part, to the threat of BA strikes.

It has become customary for the Pope to return home from official visits on the flag carrier of the country he has toured. 

But Pope Benedict will instead fly from Rome to Britain and back on an Airbus A320 operated by Italian state airline Alitalia.

One factor understood to have concerned Roman Catholic officials was the BA cabin crew strikes, which threaten to restart in September when the visit takes place.

The Vatican is determined nothing should detract from the four-day trip, the first state visit by a Pope to Britain.