This Morning host Holly Willoughby was left with her bottom on full display after her pesky dress split right up the back

There’s no good time to have a wardrobe malfunction, but we imagine in the middle of a posh party at 10 Downing Street is less than ideal.

So spare a thought for poor Holly Willoughby who was left with her whole BUM hanging out as she attended a swanky do hosted by the Prime Minister’s wife, Samantha Cameron, last night.

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Holly recounted how a pesky zip on her dress left her in a ‘very embarrassing’ situation live on Wednesday’s instalment of This Morning.

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Reliving the evening’s events, she told viewers: ‘As soon as we walked through that lovely famous black door, I gave my coat and I gave my phone in because you’re not allowed to have your phone.’

And then came the nightmare moment: ‘I went to the loo, stood up, then I heard this noise and my zip on the back of my dress went completely.’

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‘Now this isnt just a little zip, this zip goes from top to bottom,’ she added as a shot of her oh-so-embaraassing wardrobe malfunction was shown on screen.

‘So I am now stood there with no coat, no phone, in the toilet in downing street, on my own thinking, ‘what do I do? I cant walk out. my bum is out!’

Thankfully a nice lady came along and Holly asked her to go and fetch her husband, Dan Baldwin – who found the whole thing highly entertaining!

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‘Dan went downstairs and thought this was hilarious, told the majority of people he met along the way included all the staff who recommended I use gaffer tape to strap my dress up or safety pins.’

She added: ‘I had to walk around my coat all night.’

And asked what SamCam said when she heard the story, Holly revealed: ‘She just went, ‘oh gosh!”

Hols went on to thank the lady who fetched her husband – who happened to be a journalist from the Daily Telegraph – for ‘saving my bacon and my embarrassment.’

As the story came to a close, co-host Phillip Schofield quipped: ‘I still think you should have walked around Downing Street with your bum out!’

Cheeky!

Watch Holly tell her embarrassing wardrobe malfunction story below