Liam Payne has revealed he was recently hospitalised with a "serious" kidney infection.
The former One Direction singer, who was due to embark on a tour around South America next month, announced he had been forced to postpone the shows while he recuperated from the infection.
"It's with a heavy heart I have to tell you that we have no other choice but to postpone my upcoming tour of South America," he wrote on Instagram. "Over the past week I've been in hospital with a serious kidney infection. It's something I wouldn't wish on anyone, and doctors orders are that I now need to rest and recover."
The 29-year-old star added he had been "beyond excited" to get on stage as he expressed his upset over the postponement.
Liam assured any fans who had already bought tickets would be reimbursed. The Strip That Down singer went on to thank his supporters for their understanding and loyalty.
"To all of you who have bought tickets, I'm so sorry," he added. "We're working to reschedule the tour as soon as we possibly can, but for now we will be refunding the tickets...
"Thanks as always for the love and support, and look forward to seeing you soon."
In an accompanying video message, Liam admitted he had felt "a little bit unwell" in recent weeks. He revealed the "best people" had been overseeing his medical treatment.
The tour was scheduled to start in Peru on 1 September, before continuing to Colombia, Brazil, Argentina and Mexico.