Ulrika Jonsson has hit back at criticism of her weight after she appeared shockingly thin and unsteady on her feet during a recent television appearance.

The star performed on BBC One's Let's Dance for Sport Relief and her gaunt appearance caused a storm on Twitter as viewers took to the social networking site to express their concern.

However, former weather girl Ulrika insists it is a "miracle" she was able to perform as she suffers from debilitating back pain.

Speaking to the Daily Mail, she said: "For the record, I am not underweight. And I do suffer from a debilitating chronic back condition.

"It was a miracle I was able to take part at all. And with only four rehearsals, I reckon we did a b**ody good job."

The star went some way to explaining her wobbly appearance following her routine on the show, blaming her footwear on her unbalanced stance.

During her appearing on the programme last week, she said: "I don't walk well in high heels - let alone dance in them."

Ulrika also sparked concern for her weight at the British Comedy Awards in London in December when she looked painfully thin as she walked along the red carpet.

The star recently admitted she struggled to maintain a healthy appetite due to her painful back problems.

She said: "I had lost my hunger not just for food, but for life. Food is a happy thing for me and I was desperately unhappy, so there was no quick fix solution of hearty meals."

BRIT AWARDS RED CARPET GALLERY

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