LONDON: Singer-actress Miley Cyrus, scheduled to perform on former American boxer Muhammad Ali’s birthday, is suffering from a bout of ill health.

Cyrus willl hit the stage with Lionel Richie, Rascal Flatts and actress-turned-singer Rita Wilson at Celebrity Fight Night in Arizona Saturday. The performance will be part of Ali’s 70th birthday celebrations, reports femalefirst.co.uk

"Laying in bed sooooo sick, send me positive energy! Gotta get healthy before celebrity fight night! Everything hurts," tweeted the 19-year-old.