"The Oscars sat me down beforehand and said they didn't want me to do anything out of order, they wanted me to actually just present it as myself," Baron Cohen said in an interview with ITV's Good Morning Britain in the U.K. "But luckily my wife put on the Ali G beard in the disabled toilets and I managed to get away with it."
Baron Cohen's wife Isla Fisher added that they locked themselves in a bathroom for 40 minutes before the bit as they applied his fake goatee, deflecting inquiries by claiming he had food poisoning.
Baron Cohen also said that he was worried that the stunt would not be well-received, but that he saw Chris Rock backstage and the host approved, so he went ahead with it.
Ali G, a character Baron Cohen originated on his 2000 series Da Ali G Show, is a white man who thinks he's black. He made fun of the diversity debate around this year's Oscars, calling himself "just another token black presenter" and introduced Best Picture nominee Room as "a movie about a roomful of white people."
The Academy of Motion Picture Arts and Sciences and ABC have not commented on Baron Cohen's statement as of press time.
Baron Cohen has a history of awards-show stunts both planned and unapproved. In 2012, while in character as The Dictator, he dumped what he claimed were North Korean dictator Kim Jong-Il's ashes on Ryan Seacrest, for which Seacrest still has not forgiven him. In 2009 he put his nearly-naked butt in Eminem's face in character as Bruno during a bit on the 2009 MTV Movie Awards that was meant to seem unplanned but was actually pre-rehearsed.
Watch the appearance in question: