Paul Carey, on behalf of Shirley Bassey said: "The Dame is hugely disappointed and was looking forward to the show immensely."
Dame Shirley came to fame many years back in the late ‘50s with hits like Big Spender and History Repeating.
Shirley Bassey sang at Glastonbury festival last summer, after arriving in a helicopter and wearing diamond-studded Wellington boots.
Troubled singer Amy Winehouse, who has also been recovering from illness, is however expected to perform at the festival this weekend.
