American actor Sylvester Stallone traveled to the Vatican on Friday for a brief private audience with Pope Francis.

When told by the pope's interpreter "We grew up watching your films", the Rambo and Rocky star raised his fists and asked the pontiff "Are you ready to box?"

In return, Francis also raised a fist with a smile.

Some of Stallone's best-known work includes his title role in the critically acclaimed Rocky film series, where he starred as underdog boxer Rocky Balboa.

He also portrayed traumatized soldier John Rambo in the action franchise Rambo, which spanned four decades.

Stallone was accompanied on the Vatican visit by his wife, daughters, and brother.

The Oscar nominee has Italian roots, with a Sicilian father who emigrated to the United States, where Stallone was born.