In the post, the Suicide Squad actor, 47, revealed that he actually chatted with Prince on Wednesday, a day before the Purple Rain star was found unresponsive in an elevator in his Chanhassen, Minnesota, studio.
"I am stunned and heartbroken," Smith wrote next to a photo of the musician playing guitar in his 1980s heyday. "I just spoke with him last night."
"Today, Jada & I mourn with all of you the loss of a beautiful poet, a true inspiration and one of the most magnificent artists to ever grace this earth," the Concussion star continued.
Will's wife, Jada Pinkett Smith, also paid tribute to Prince on Facebook. In her message, she called him a "genius artist," adding: "He showed me early the power of living one's life by one's own rules and no one else's."
Numerous public figures have taken to social media to remember the "When Doves Cry" singer, including President Barack Obama, Justin Timberlake, Lenny Kravitz, Carmen Electra and Prince's ex-fiancée Sheila E.
The autopsy is scheduled for Friday, April 22.
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