Spike Lee. (Charles Sykes/Invision/AP)

After the Academy Awards experienced serious backlash last week for a second year of all-white acting nominees (also known as #OscarsSoWhite), celebrities have started to speak out — and some won't be attending the Oscars as a result.

On Monday, director Spike Lee and actress Jada Pinkett Smith posted messages to social media explaining that they would skip the Oscars ceremony because of a lack of diversity. Lee, awarded an honorary Oscar in November, directed the acclaimed "Chi-Raq," which didn't receive any nominations. Smith's husband Will Smith, who garnered awards buzz (and a Golden Globe nod) for his lead role in "Concussion," was also left off the Oscars list.

[Audiences show up to movies with people of color. So why are #OscarsSoWhite again?]

In an Instagram post, Lee thanked film academy president Cheryl Boone Isaacs for last year's honorary trophy, but said that after last Thursday's nominations, he and his wife will not be attending the show.

"We Cannot Support It And Mean No Disrespect To My Friends, Host Chris Rock and Producer Reggie Hudlin, President Isaacs And The Academy. But, How Is It Possible For The 2nd Consecutive Year All 20 Contenders Under The Actor Category Are White?" Lee wrote, noting it was a timely question to ask on Martin Luther King Jr. Day. "And Let's Not Even Get Into The Other Branches. 40 White Actors In 2 Years And No Flava At All. We Can't Act?! WTF!"

Lee added that nothing will change until there's more diversity in Hollywood's executive suites. As he said in his November Oscar speech, the only black people he sees in movie studios are the security guards. "The Truth Is We Ain't In Those Rooms And Until Minorities Are, The Oscar Nominees Will Remain Lilly White," Lee wrote.

[Who picked these #OscarsSoWhite nominees? Other white people.]

Meanwhile, Smith posted a video to Facebook and also brought up Martin Luther King Jr. Day, asking: "Is it time that people of color recognize how much power, influence that we have amassed, that we no longer need to ask to be invited anywhere?"

We must stand in our power!We must stand in our power.

Posted by Jada Pinkett Smith on Monday, January 18, 2016

Smith, who had tweeted earlier wondering if people of color should refrain from attending the Oscars, made her decision. "Begging for acknowledgment or even asking diminishes dignity and diminishes power. And we are a dignified people and we are powerful and let's not forget it," she said in the video. "So let's let the Academy do them, with all grace and love, and let's do us differently. I got nothing but love."

She wrapped up with a shout-out to upcoming host Chris Rock, who referred to the Oscars as the "White BET Awards" last week. "Hey Chris, I will not be at the Academy Awards and I won't be watching, but I can't think of a better man to do the job at hand this year than you, my friend. Good luck," Smith said.

The academy did not respond to a request for comment about Lee and Smith. Last week, academy president Isaacs told Deadline she was "disappointed" that films such as "Beasts of No Nation" starring Idris Elba and hip-hop epic "Straight Outta Compton" were left out. "This has been a great year in film, it really has across the board. You are never going to know what is going to appear on the sheet of paper until you see it," she said. And in regards to the academy trying to diversify its ranks by extending invitations to a wider variety of members (the academy is about 93 percent white and 74 percent male), Isaacs said, "We have got to speed it up."

Read more:

#OscarsSoWhite, but here are 8 great 2015 performances by black Oscars

Diverse movies are a huge business. Why doesn't Hollywood make more?

Oscar nominations: Diverse in some ways, stuck in a rut in others