Peter O’Toole, the venerable actor perhaps best known for his title role in “Lawrence of Arabia” 50 years ago, announced on Tuesday that he was retiring from acting.

“The heart for it has gone out of me: it won’t come back,” Mr. O’Toole, 79, said in a statement released by a publicist.

Mr. O’Toole’s career included playing several key Shakespearean roles including “Hamlet,” and roles in “Goodbye, Mr. Chips,” “The Ruling Class,” “The Stunt Man” and “My Favorite Year,” among many other films. He earned eight Academy Award nominations without winning an Oscar but was given an honorary one in 2003.

His achievements “brought me public support, emotional fulfillment and material comfort,” Mr. O’Toole said in his statement. “It has brought me together with fine people, good companions with whom I’ve shared the inevitable lot of all actors: flops and hits,” he said.

“However,” he added, “it’s my belief that one should decide for oneself when it is time to end one’s stay.”