In an statement posted on his Instagram on Monday, Smith said that his behaviour was "unacceptable and inexcusable."
"Violence in all of its forms is poisonous and destructive. My behavior at last night’s Academy Awards was unacceptable and inexcusable. Jokes at my expense are a part of the job, but a joke about Jada’s medical condition was too much for me to bear and I reacted emotionally.
"I would like to publicly apologize to you, Chris. I was out of line and I was wrong. I am embarrassed and my actions were not indicative of the man I want to be. There is no place for violence in a world of love and kindness," wrote the actor, who won the Best Actor Award for his role in "King Richard", later at the same ceremony.
Smith further apologized to the Academy, the producers of the show, as well as the attendees and viewers around the world, for his conduct.
"I deeply regret that my behavior has stained what has been an otherwise gorgeous journey for all us. I am a work in progress," Smith wrote.
Smith slapped Rock after the latter poked fun at Smith's wife, Jada Pinkett Smith's shaved head, by saying: shaved head."Jada I love you, 'G.I. Jane 2,' can't wait to see it."
The joke did not seem to go well with Jada, who was seen rolling her eyes in disgust at the joke. She has been open about her struggle with alopecia, a form of autoimmune disease that leads to hair loss.
Although Smith was initially seen laughing to the joke, he later stood up, walked to the stage and slapped Rock on the face.
The actor also later told Rock to "keep my wife's name out of your f***ing mouth!"
Although shaken at first, Rock then went on to present the award to the best documentary.
Rock has refused to press charges against Smith.
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