Britney Spears walked off the US 'X Factor' set after a contestant dressed in drag covered one of her songs.

The 30-year-old judge wasn't impressed when the male wannabe - who was dressed partially as a woman in glasses and a jean jacket - attempt to sing her 1999 hit '(You Drive Me) Crazy' at auditions for the talent show in Greensboro, North Carolina, so much so she fled the judges table and joined her husband, Jason Trawick, in the production area.

Following the performance on Monday, fellow panellist Simon Cowell - who covered his face with his hands throughout the rendition - told the US 'X Factor' hopeful that the blonde beauty had failed to "understand" his tribute.

He said: "I don't think she quite understood your tribute. You've got to be able to sing in tune. There wasn't a note in tune."

Britney eventually returned to the stage and insisted she "respected" the wannabe's tribute, but she wasn't keen for him to progress to the next round of the talent show.

She told him: "I really respect the tribute. It was really nice, but I just don't feel like it's for 'X Factor'. Sorry, sweetie."

Fellow judges L.A. Reid and Demi Lovato followed Britney off stage and didn't return to give their opinions on the contestant's performance.

It's not the first time Britney has walked off following an audition as last month she was joined by L.A., Demi and stand-in judge Louis Walsh - who was sitting in for an ill Simon - in Kansas City when all four stormed off set when a contestant performed with his back to the panellists.