Hollywood action hero Bruce Willis, star of the ‘Die Hard’ franchise, is to retire from acting due to an illness affecting his cognitive faculties, his family announced Wednesday, reports AFP.

A post on Instagram signed by his family said Willis had developed aphasia -- a language disorder that robs people of their ability to communicate.

"As a result of this and with much consideration Bruce is stepping away from the career that has meant so much to him."

Aphasia is typically caused by a stroke or head injury -- though in more rare cases can come on gradually and progressively.

The condition affects a person's ability not just to speak and understand verbal communication but also their reading and writing.

Willis has been a fixture on the small and large screen since the 1980s, coming to public prominence with the TV series "Moonlighting."