Nicki Minaj was forced to cancel her appearance at V Festival at the weekend after being urged to rest her voice, her representative said.
The US rapper had been due to headline the 4Music stage on August 18 and 19 at Hylands Park in Chelmsford, Essex and Weston Park in Staffordshire.
Minaj’s representative confirmed the 29-year-old artist had pulled out of the shows because of “strained vocal cords”.
Earlier last week, Minaj apparently ignored doctors’ advice to rest her voice and performed for fans in New York in a two-hour gig that also featured Drake, Lil Wayne and Foxy Brown.
After last Wednesday's concert she tweeted, "Its official, my voice is GONE!!!! I swear it held up just to spk to u guys last nite! Mind over matter. The mind is so powerful".
Her representative said her voice had got "worse", and that recent X-rays revealed that the singer must rest it for a few days.
In a statement, V Festival organisers wished Minaj a “speedy recovery” and explained that the Starships singer had felt unwell as she boarded her flight from New York on Friday night.
“This is despite having thought she had overcome her vocal cord issues from earlier in the week,” the statement said.
“Having revisited her doctor she has now been advised to rest for a week, which unfortunately means that she is no longer able to perform at V Festival.”
LMFAO filled Minaj’s slots at the two-day festival, which also saw The Killers, David Guetta and The Stone Roses perform.
Minaj's second album Pink Friday: Roman Reloaded topped the charts in the UK and US. Her Pink Friday Reloaded tour is due to kick off on October 21 in Nottingham, with dates in Manchester, Liverpool, Newcastle, Birmingham, London, Sheffield and Cardiff.