Poor old Katherine Jenkins will be mortified by her recent wardrobe malfunction.

The opera singing beauty has turned down lucrative offers from Playboy and other lad mags but unwittingly revealed her nipple to excited fans at Manchester MEN arena this week.

The Popstar To Operastar judge was taking part in a high flying trapeze act during her concert, when she leaned backwards and popped out of her outift.

One fan told The News Of The World: “She was taking a risk by wearing something so daring. Poor Katherine would have been mortified – she’s modest and has turned down huge offers to strip for mags like Playboy.”

To see the revealing pic, click here.