The comic announced his decision on Twitter, contending that, "I do not want to be a distraction on a night that should be celebrated by so many fantastic talented artists".
Kevin Hart had said hosting the Oscars was "a goal on my list for a long time".
Then on Thursday, Hart said on Instagram he would not apologize and stressed that people change.More news: China to 'immediately' implement United States trade truce measures
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Kevin Hart took to Instagram on Thursday after old tweets resurfaced that included homophobic expressions. "The reason why I've passed is that I've addressed it several times". I've said where the rights and wrongs were. Hart has since spoken about the joke, telling Rolling Stone in 2015 that it was really about his "own insecurities" as a parent, again reiterating he's not homophobic and saying he "wouldn't tell that joke today, because when I said it, the times weren't as sensitive as they are now".
Hart's attitudes about homosexuality were also a well-known part of his stand-up act.
In the video, Hart criticized "internet trolls" for digging up his old tweets and said, "The same energy that went into finding those old tweets is the same energy that could have been put into finding the response to the questions that have been asked years after years".
"Guys, I'm nearly 40 years old", he said in a video Thursday. In the 2010 special "Seriously Funny", he said "one of my biggest fears is my son growing up and being gay". Hart said he "loves everybody". 'Like I tweeted a few weeks ago, Hollywood still has a real problem with gay men. On the surface it may not look like it.
The Motion Picture Academy did not immediately have a comment on whether they had demanded Hart apologize and if they planned to dump him.
But would he still be busy loving his kids if one of them came out as gay?
With the entertainment industry at the fore of societal change amongst the #MeToo era, having an Academy Awards host who not only has a past riddled with latent homophobia, but refuses to acknowledge or apologise for it, is a backwards step.