Hollywood star Sylvester Stallone has been fined $2,500 by an Australian court for illegally importing a human growth hormone to the country.

The court was told that the 60-year-old actor had been prescribed the banned hormone to give his aging body a boost before filming the latest 'Rambo' movie.

Stallone told customs: "This stuff gives your body a boost and you feel and look good. Doing 'Rambo' is hard work, and I am going to be in Burma for a while."

"Where do you think I am going to get this stuff in Burma?," the actor asked.

Stallone apologised to Australian authorities and pleaded guilty to two charges of importing a prohibited substance.

His lawyer said that the actor was taking the hormone under doctors' supervision for an undisclosed medical condition.

Lawyer Phillip Boulten said: "This is not some back-alley bodybuilder dealing covertly with some banned substance in some sort of secret way."