American actor James Avery, best known as Will Smith's Uncle Phil in television show The Fresh Prince of Bel-Air, has passed away at the age of 68.

Avery's publicist Cynthia Snyder told The Associated Press that he passed away in California, due to complications from open-heart surgery.

According to ShowbizSpy, Smith was "devastated" after finding out the news by phone.

"Will was ringing in the New Year with his family when an associate told him the news. Working with James was a big part of his life.. in fact, James was something of a father figure to Will. He's devastated by the death. James will be sorely missed," an insider said.

Smith's wife, Jada Pinkett-Smith took to her Facebook page to pay tribute to the actor.

"Happy New Year everyone! I was hoping to start the new year differently but we have lost yet another friend. James Avery who we all lovingly know as Uncle Phil from The Fresh Prince has passed," she wrote, adding, "Our condolences to aunt Florence (his mother), Miss Barbara (his wife) and all those who loved him. Rest in peace James."

Alfonso Ribeiro, Avery's son on the hit sitcom, posted: "The world has lost a truly special man. I am very saddened to say that James Avery has passed. Even though he played my father on TV, he was a wonderful father figure to me in life. He will be deeply missed.

"R.I.P James Avery" and "Uncle Phil" have been trending on Twitter, with celebrities and fans paying tribute to the actor.

American singer Ray J tweeted: "R.I.P James Avery, Prayers go out to his family #sadnews"

Scrubs actor Zach Braff wrote: "James Avery was a very funny and smart man. He did a cameo as a favour to me in WIWH and had the entire set rolling with laughter. RIP."

Actress Tatyana Ali posted: "James was my teacher my protector & the most magnificent actor. We're feeling his loss very deeply. He'll always be a part of me #JamesAvery"