The former sports broadcaster has made a name for himself in the U.K. for his bizarre theories, claiming the world is governed by lizards, and his videos promoting notions about the COVID-19 virus have recently been removed from Facebook.
However, according to Britain's Daily Star newspaper, Williams is a fan, and has been quoted as saying, "I've met David quite a few times, I like him, I like his message, I like what he's got to say."
A representative of U.K. anti-extremism group Hope Not Hate, who has led calls for Icke to be banned from social media for stirring up anti-Semitic conspiracies and false COVID-19 theories, has slammed the singer for his supportive comments.
"David Icke has long been known as a spreader of conspiracy theories, and it's a mistake for anyone to categorise him as merely an outlandish and eccentric freethinker," a spokesperson tells WENN. "In fact, he is one of the largest promoters of harmful misinformation about COVID-19 and conspiracies of world domination by Jewish people."
Williams, who reportedly first met Icke more than a decade ago, was also quoted as saying he trusts the conspiracy theorist more than government experts.
"I know whose spirit I identify with more. Does that mean he's right? I don't know," the "Angels" hitmaker is quoted as saying. "But if you put a gun to my head and say, 'Pick one' - I'm not choosing them..."
His comments have also upset Jewish activists and a representative of the Campaign Against Anti-Semitism tells WENN Icke is an "anti-Semitic hate preacher."
"It is imperative that celebrities and others in positions of influence examine more carefully the figures they choose to endorse, otherwise they risk drawing more impressionable people into the orbit of hateful nonsense polemicists," the spokesperson warns.
Robbie's aides have yet to respond to requests for comment.