"I would like to publicly apologise to you, Chris," he said in a statement. "I was out of line and I was wrong."

It comes after the Oscars film academy condemned Smith over the incident and announced a formal review.

The star slapped Rock in the face on stage after the comic made a joke about the actor's wife, Jada Pinkett Smith.

Rock had taken aim at Pinkett Smith's shaved head, a result of the hair-loss condition alopecia.

I deeply regret that my behaviour has stained what has been an otherwise gorgeous journey for all of us," he wrote.

Prior to Smith's apology, the organisation behind the Oscars said in a statement that it "condemns the actions" of Smith.

"We have officially started a formal review around the incident and will explore further action and consequences in accordance with our Bylaws, Standards of Conduct and California law," it said.