The American singer was due to perform at Livewire Festival on 24 August over the bank holiday weekend, alongside Matt Goss and Boyz II Men.

A festival spokesman said the event had been "postponed until 2019" due to the ill-health of "key personnel" within promotion company Livewire Events.

Ticket holders have been advised to seek refunds from ticket vendors.

Country music legend Kenny Rogers earlier pulled out of the festival after revealing he was "working through a series of health challenges".

Writing on Twitter, Laura Bently said: "Gutted, but why are we only getting face value refunds? What about booking fees?"

Valerie Monsanto said "Is this for real? Omg", while Natalie Oldfield added: "Can we get our hotel refunded?"

Tara Wells posted on Facebook: "That's poor!"