Hollywood tough nut Bruce Willis has confessed that he's finding it harder to do the stunts he was famed for in his youth.

The 52-year-old said that one stunt in the forthcoming Die Hard 4.0 almost left him without an eye.

"I took a kick to the head," Willis said of one particularly damaging stunt for the film.

"Half a second earlier and it would have taken my eye out. I love all the physical stuff, but the recovery time is a lot longer these days.

"Other guys have taken everything up to another level, doing things I've never seen anybody do."

It has been 12 years since the actor appeared in a Die Hard film.

In the soon to be released film he takes up the role of veteran New York cop John McClane as he battles against a gang of international criminal hackers.