David Oyelowo David Oyelowo

Even as the Academy of Motion Picture Arts & Sciences is vowing to take "dramatic steps" to diversify its Oscar nominees in future years, more stars are speaking out about the fact that the 2016 acting nominees do not include any people of color.

David Oyelowo, who was passed over by the Academy last year for playing Dr. Martin Luther King Jr. in Selma, said of the nominations: "I am an Academy member and it doesn't reflect me. It doesn't reflect this nation."

On Twitter, actor Don Cheadle reached out to Oscars host Chris Rock, joking that he'll be working as a parking attendant at this year's ceremony.

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George Clooney also weighed in, saying the Oscars are "moving in the wrong direction" and noting that the problems extend beyond the lack of nominees. "I don't think it's a problem of who you're picking as much as it is: How many options are available to minorities in film, particularly in quality films?" Clooney asked. "I think that African Americans have a real fair point that the industry isn't representing them well enough. I think that's absolutely true. ... There should be 20 or 30 or 40 films of the quality that people would consider for the Oscars. By the way, we're talking about African Americans. For Hispanics, it's even worse. We need to get better at this. We used to be better at it."

The comments come on the heels of criticism from stars including Spike Lee and Jada Pinkett Smith, both of whom have called for a boycott of the Oscars. On Tuesday, Academy President Cheryl Boone Isaacs, who is black, said in a statement that she is "both heartbroken and frustrated" by the field of nominees, and called for "big changes" in the way the Academy recruits its members.