James Lee Williams, better known as drag queen The Vivienne, has died aged 32.
Publicist Simon Jones said the performer, who died over the weekend, was "an incredibly loved, warm-hearted and amazing person".
The Vivienne won the first series of RuPaul's Drag Race UK in 2019.
Mr Jones asked for privacy for the star's family and said no further details would be released at this time.
RuPaul's Drag Race judge Michelle Visage said she was "utterly heartbroken" at the news of The Vivienne's death.
Writing on social media, Visage wrote: "I don't have the words. Utterly heartbroken."
RuPaul's Drag Race UK star Bimini Bon Boulash reacted to the news, writing on Instagram: "I'm so sorry I'm in total shock".
Cheryl The Queen - who used to go by Cheryl Hole - took part in the same series of Drag Race as The Vivienne. She also shared the statement on Instagram, writing: "I will love you forever Viv."
Mr Jones said these were words he "never ever wanted to write".
"No one has ever made me laugh in my life as much as Viv did. Their comic genius and quick wit was like no other," he said.
"I'm so proud and lucky that Viv was such a big part of my life every day for the last 5 years."
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