The lead singer of US band Matchbox Twenty has been forced to apologise after making a racist joke about Aboriginal drinking during a solo performance in Melbourne, sparking outrage among fans and within the Indigenous community.

Rob Thomas, who fronts the multi-platinum selling rock band, was speaking to the crowd about how he deals with jet lag when he made the remarks, which caused groans and booing from the crowd.

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“I’ve got the jet lag figured out,” he said during the show.

“What you do is, when you get on the plane on your way here, you start drinking. And then I drink until I think I’m Australian.”

The crowd began to cheer, but then Thomas added: “And I keep drinking until I think I’m a black Australian.”

Fans swiftly took to social media to express their disgust.

Bloody hell, Rob Thomas. You don’t have to study Australian racism to know that that ‘joke’ was racist.

— Joshy20(1)6 (@Joshy206) February 21, 2016

Twitter user Lindsay McDownes said: “Imagine drinking so much you actually become Rob Thomas.”

Matt Osborn tweeted: “I don’t know which I am more surprised about: #robthomas’ ignorant and awful remarks, or that he is still doing shows #the90sareover”

Following the backlash, the singer issued a full apology on Facebook, claiming he was unaware that the comment could have been offensive.

The apology triggered both supportive and angry responses. One Indigenous commenter said his culture helped him to overcome things like racial insults.

But not everyone was so understanding.

However, the apology received support from fellow band member Paul Doucette, who wrote: “I can 100% assure you that @ThisIsRobThomas is not racist in any way & that no harm was meant. I can also assure you that he is devastated.”

But that was not enough for award-winning Australian Indigenous artist Troy Cassar-Daley, who slammed the performer, suggesting his opinion of Thomas had been changed by the incident.

“Thomas always came across as a smart Bloke to me, I guess I was wrong,” he said.