Heartbroken at the loss of my beloved friend Yog. Me, his loved ones, his friends, the world of music, the world at large. 4ever loved. A xx https://t.co/OlGTm4D9O6
— Andrew Ridgeley (@ajridgeley) December 26, 2016
"Farewell my Friend! Another Great Artist leaves us," Madonna wrote in a post on Instagram accompanied by a video of her presenting Michael with an award.
Elton John also published a picture of himself with Mr Michael:
In the United States, Recording Academy president Neil Portnow said he was "deeply saddened" by the loss. "During an influential career that spanned nearly four decades, George became one of the most beloved pop craftsmen and respected entertainers," said Mr Portnow, whose organisation awards the Grammies. "From the enormous success he achieved with pop duo Wham! to his influential solo career, his extraordinary talent had a profound impact on countless entertainers worldwide, and his creative contributions will live on forever," he said.
Canadian musician Bryan Adams, Robbie Williams and others tweeted:
RIP George Michael. I can't believe it. Such an incredible singer and a lovely human being, far too young to leave us #georgemichael
— Bryan Adams (@bryanadams) December 25, 2016
Oh God no ...I love you George ...Rest In Peace x
— Robbie Williams (@robbiewilliams) December 26, 2016
You have given the #world an amazing gift! What a #talent! What a #loss! We will continue to love you! #RIP George Michael! pic.twitter.com/plb7KjXOaP
— La Toya Jackson (@latoyajackson) December 26, 2016
Duran Duran, who were 1980s contemporaries of Wham!, said on Twitter:
2016 - loss of another talented soul. All our love and sympathy to @GeorgeMichael's family. pic.twitter.com/3h4xqEDXR9
— Duran Duran (@duranduran) December 25, 2016
Spandau Ballet, a British band which formed in the late 1970s, wrote:
We are incredibly sad at the passing of our dear friend George Michael. A brilliant artist & great songwriter. Spandau Ballet / Steve Dagger
— Spandau Ballet (@SpandauBallet) December 25, 2016
Tributes came in from outside the music world too:
I just heard about my friend @GeorgeMichael's death. He was such a brilliant talent. I'm so sad.
— Ellen DeGeneres (@TheEllenShow) December 25, 2016
So sorry to hear about George Michael's passing. Brilliant icon. "Kissing a Fool" one of my all time favs. Strength & light to his family.
— Dwayne Johnson (@TheRock) December 26, 2016
George Michael was a kind and gentle soul. #Wham
— Ryan Reynolds (@VancityReynolds) December 26, 2016
Unbelievable.
— Ricky Gervais (@rickygervais) December 25, 2016
RIP George Michael.
This Christmas is beautiful yet sad as I remember @GeorgeMichael and his amazing talent and the beauty he created with songs.
— Tyra Banks (@tyrabanks) December 26, 2016
Rest with the glittering stars, George Michael. You've found your Freedom, your Faith. It was your Last Christmas, and we shall miss you.
— George Takei (@GeorgeTakei) December 25, 2016
I've loved George Michael for as long as I can remember. He was an absolute inspiration. Always ahead of his time.
— James Corden (@JKCorden) December 25, 2016
George Michael was due to release a documentary in 2017. For the longest time he lived outside the public glare and made news only for some drug related incident.
(With AFP inputs)