Sinéad O'Connor has cancelled all of her summer dates due to ''exhaustion''.

The 'Nothing Compares 2 U' singer has axed all of her upcoming tour dates due to a medical issue, meaning she will no longer perform at Festival Big Top in Galway, Ireland today (23.07.15) and will miss her scheduled shows in Norway and Canada.

In a statement, her agent explained: ''Sinead O'connor apologises profusely to her fans but she cannot travel this summer anymore. She is suffering from exhaustion due to an existing not resolved medical situation and she has been advised by the doctor to stop any activity and rest. Because of this she is completely unable to travel and to perform.''

The 48-year-old musician - who recently became a grandmother for the first time when her 27-year-old son Jake had a child with his girlfriend Lia - hit the headlines last week when she blasted Rolling Stone magazine for putting reality TV star Kim Kardashian West on the cover, claiming the move meant ''music has officially died''.

In a furious rant on her Facebook page, which has since been deleted, she wrote: ''What is this **** (''I don't smile much because it causes wrinkles'') doing on the cover of Rolling Stone? Music has officially died. Who knew it would be Rolling Stone that murdered it? Simon Cowell and Louis Walsh can no longer be expected to take all the blame. Bob Dylan must be f**king horrified #BoycottRollingStone (sic).''