Sinéad O'Connor in concert on the first night of the Toender Folk Music Festival in Toender. File/AP

Irish singer Sinead O'Connor, known for topping the charts around the world with the 1990 song "Nothing Compares 2 U", has died at the age of 56, Irish national broadcaster RTE quoted her family as saying on Wednesday.

"It is with great sadness that we announce the passing of our beloved Sinead. Her family and friends are devastated and have requested privacy at this very difficult time," RTE quoted a statement from the singer's family as saying.

Brash and outspoken - her shaved head, pained expression, and shapeless wardrobe a direct challenge to popular culture's long-prevailing notions of femininity - O'Connor changed the image of women in music in the early 1990s.

Sinead O'Connor poses for a photograph. File photo

She crashed onto the global music scene at the beginning of the decade with her mesmerizing version of the song originally written by Prince, facing directly into the camera for the music video that has subsequently been viewed almost 400 million times on YouTube.

She will be remembered in some quarters for ripping up a photo of Pope John Paul II during a television appearance on "Saturday Night Live."

"Everyone wants a pop star, see?" she wrote in her 2021 memoir "Rememberings". "But I am a protest singer. I just had stuff to get off my chest. I had no desire for fame."

O'Connor converted to Islam in 2018 and changed her name to Shuhada Sadaqat, though continued to perform under the name Sinead O'Connor.

Ireland's President Michael Higgins said Ireland had lost "one of our greatest and most gifted composers, songwriters and performers of recent decades".

He praised O'Connor's "fearless commitment to the important issues which she brought to public attention, no matter how uncomfortable those truths may have been".

Irish Prime Minister Leo Varadkar said O'Connor's "music was loved around the world and her talent was unmatched and beyond compare".

"Condolences to her family, her friends and all who loved her music," he added.

"It is hard to think of an artist who has had the social and cultural impact of Sinead," Colm O'Gorman, executive director of Amnesty International Ireland wrote in reaction to her death.

"What a loss. Heartfelt condolences to her children, her family and all who loved her," he added.

O'Connor had also spoken publicly about her mental health struggles, telling Oprah Winfrey in 2007 that she struggled with thoughts of suicide and had been diagnosed with bipolar disorder.

More recently she had shunned the limelight, in particular following the death of her son Shane from suicide last year at the age of 17.

O'Connor is survived by three children and had reportedly been dividing her time between Ireland and Britain prior to her death.

Reuters