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Sam Smith

Sam Smith has been forced to scrap a series of performances, including a set at the Billboard Music Awards, to focus on his health.

Just days after the singer cut short a gig in Cape Town, South Africa last week and told fans he was struggling with anxiety issues, he has axed a string of appearances.

A statement on his Twitter page reads: "In the wake of cutting his South African tour short last week, Sam's medical specialists are requiring him to have further rest. Regrettably this means that he will be unable to perform at the Azerbaijan Gran Prix in Baku this weekend or the Billboard Music Awards in Las Vegas next week.

"We apologize for the disappointment for those affected, but the primary focus at this time needs to be on Sam's recovery and health."

The Stay With Me star took to his Instagram Story account after the Cape Town concert last week and wrote: "The last week, or so I've been doing these incredible shows, and from my pics, I look super happy and calm and collected, and I am happy, and sometimes I am calm. But the last few weeks my anxiety has been SO F***ING INTENSE!! I can't even begin to explain.

"I've felt completely out of control and as if I'm going to snap and everything is going to come undone. However, for the first time ever I have been trying to really tackle and fight against these horrible thoughts and tidal waves of fear."

His post prompted fans to send him their best wishes via social media, with one writing: "Get well soon and please please take care of yourself!! I'll be waiting for you whenever you're ready."