Dressed in military white uniform and a huge false beard the comedian had come dressed in character. He was also flanked by two models in dictator-style combat uniform. Cohen was carrying an urn with a picture of recently deceased former North Korean leader Kim Jong-Il on it.
During an interview with American TV host Ryan Seacrest, he claimed they were the genuine ashes of the North Korean leader and his dying wish was "to be sprinkled over the red carpet and over Halle Berry's chest". He then poured the contents of the urn over Seacrest's head, sprinkling the TV host's tuxedo in white dust. Seacrest then open-mouthed to the camera said: "Anything can happen and it most certainly did, all over my lapel"!
Baron Cohen had been on the guest list to attend the Oscars thanks to his appearance in Hugo, a Martin Scorsese film nominated in several categories.
But after the ashes stunt Baron Cohen was bundled off by security guards. The Dictator film is to be released in March and follows in the footsteps of previous blockbuster movies Borat and Bruno, reports the BBC
The Borat-fame comedian also stoked controversy in the days leading up to the Academy Awards when rumours surfaced he was planning on walking the red carpet as General Aladeen, the fictional despot he plays in his new film. The Oscars usually frown on self-promotion and certainly would not have sanctioned the stunt.
During the ceremony itself Cohen was thrown into the air wearing a harness and fell awkwardly into the lap of US rap-musician Eminem, who then proceeded to storm out. There are reports however that the Lose Yourself-singer was in on the act
You can see a complete list
of who went home with an Oscar in the 84th annual award ceremonies. Meanwhile Cohen will have to wait until next year to see if his new film will achieve any nominations.