The mezzo-soprano, who was made a dame in 2017, said "imminent surgery" left her unable to attend the concerts.

"I hope, however, to fulfil all of my other concert and recording commitments over the coming months," she added.

The star's illustrious career has included appearances at Glyndebourne and the Last Night of the Proms.

She had been due to star in the ENO's Orpheus and Eurydice, which is choreographer Wayne McGregor's opera directing debut, this October.

Alice Coote will step in to play the role of Orpheus, while Julie Boulianne will now take her place at the BBC Proms, singing Berlioz's The Childhood of Christ.

Born in County Durham in 1963, Dame Sarah studied piano and singing at the Royal College of Music, of which she is now a fellow. She was made a dame in 2017.

As a soloist, she became known as a singer of opera's so-called "trouser" roles - women playing boys or men - and got her big break playing Handel's petulant emperor Xerxes in Nicholas Hytner's English National Opera production in 1998.

She's sung at the Metropolitan Opera, the Opéra national de Paris and the Teatro Réal in Madrid, and poked fun at her masculine roles by singing Rule, Brittania! dressed as an Admiral of the Fleet at 2009's Last Night of the Proms.

In a statement announcing her temporary withdrawal from the stage, Dame Sarah said: "Last month, I had an unwelcome birthday present, breast cancer.

"Like so many women afflicted with this disease, I will face whatever is coming as best I can.

"I'd like to thank the BBC Proms and the ENO for their kindness and understanding, and I look forward to working with them both in the near future."

In response, the BBC Proms said: "We at the Proms all wish Sarah well and are thinking of her at this difficult time."