For one heart-stopping moment it looked like Whitney Houston might bust of her sparkly silver gown during her live X Factor performance.

As she belted out new single Million Dollar Bill on Sunday's results show, a strap keeping her dress secure at the back pinged undone, leaving her cleavage dangerously close to making it's own unscheduled appearance.

Houston, we have a problem: Whitney struggling with her wayward straps

After briefly fiddling around with the fastening, Whitney gave up and carried on singing, while no doubt hoping for the best.

Luckily, her modesty remained intact and she laughed off the incident afterwards, joking to host Dermot O'Leary: "I sang myself out of my clothes."

Whitney on the X Factor stage before her wardrobe malfunction

Earlier Whitney had looked every one of her 46 years - and perhaps a few more - as she arrived at the X Factor studios without any make-up.

But by the time she took to the stage - via hair, make-up and wardrobe - she was back to her fabulous best.

The original singing diva arriving at the London X Factor studios (left) and transformed by the time she steps on stage (right)

The mother-of-one and ex-wife of Bobby Brown is certainly in great shape for someone who has admitted she was once so strung out on a mixture of marijuana and crack that she forgot she was a famous pop star.

"I didn't think about the singing part anymore," she told Oprah Winfrey in her big 'comeback' interview. "I'd totally forgotten about that life. I had so much money by that time."

Thankfully, she seems to have remembered again.