Sam Smith has cancelled upcoming concerts in Birmingham and Glasgow on doctors' advice, after having to stop Wednesday's Manchester gig just four songs in due to "a vocal cord injury".
A spokesperson for the "heartbroken" star, 31, said on Instagram that medics recommended a "complete vocal rest".
"If they keep singing, they will do permanent damage to their voice," they explained. "If they take some rest, they will be able to perform again."
The singer said refunds are available.
They recently pulled out of a gig in Glasgow, on health grounds, and rescheduled it for Thursday 25 May, while the Birmingham date had also been rearranged for the following Saturday.
Ticket holders will be able to get their money back for all three now-cancelled concerts at the point of purchase.
The singer, who uses them/they pronouns, had to cut short Wednesday's gig at the AO Arena in Manchester, after having started promisingly with a performance of the hit Unholy, just hours after teasing a show "surprise" on social media.
But fans were soon left bewildered when the venue went dark, the concert ground to a halt and the star left the stage.
The crowd was then informed Smith was facing "vocal issues".
An apologetic Smith earlier explained on Instagram that they had contracted a virus several weeks ago, ahead of the European leg of their tour, but had only started to feel unwell again at the start of Wednesday's show.
"Today in soundcheck I felt fine and was so excited to give Manchester an amazing show tonight, with a special surprise at the end," they wrote.
"During my third song, I noticed something wrong with my voice. I prayed it was just my voice waking up for the show but into the fourth song I could feel something was really wrong."
Smith added: "I came off stage and have tried everything to get my voice back in gear but it won't.
"I am honestly heartbroken I couldn't finish the show tonight for you all. I love you all. I'm sorry I'm sorry I'm sorry."