Chris Rock has joked he is hosting the Oscars because Ellen DeGeneres said no.

Chris Rock

Chris Rock

The 51-year-old comedian is set to front the awards ceremony and joked he had only been given the job because 'The Ellen DeGeneres Show' host couldn't make it.

He said: "I'm only here because Ellen didn't want to do the show. I'm only here cause Ellen said no. And I'm sure she said no like eight times."

The ceremony has been surrounded by controversy this year over claims of a lack of diversity in the nominations, prompting the #OscarsSoWhite hashtag to do the rounds on Twitter.

When asked if he will make a quip at the Academy about diversity, he told The Hollywood Reporter magazine: "You can do a pretty decent monologue and be funny two or three other times throughout the show. You'll be fine. If you get off on the wrong foot though, it's a real hard hole to dig yourself out of.

"You can do a pretty decent monologue and be funny two or three other times throughout the show. You'll be fine. If you get off on the wrong foot though, it's a real hard hole to dig yourself out of."