‘This Morning’ presenter Holly Willoughby couldn’t but dissolve into giggles as her co-host Phillip Schofield showed her a newspaper story on her phone about her wardrobe malfunction at a Downing Street event the night before.

On Tuesday evening (March 1st), 35 year old Willoughby attended a reception for the charity Together 4 Short Lives, when the zip on the red dress she was wearing split from top to bottom down the back. Though she had a black undergarment on, it wasn’t quite enough to cover everything…

Holly shared the amusing photograph the next day with her followers on Instagram, strategically placing a red speech bubble to protect her modesty, and the incident found its way to the entertainment sections of news publications within a few hours.

Oops...Why does this always happen to me and at No 10 too! ?????? #zipfail #mostembarressingmoment ...

A photo posted by Holly Willoughby (@hollywilloughby) on

Indeed, when Schofield took the opportunity to embarrass his co-host live on air the following day, Willoughby reacted by sniggering uncontrollably.

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“This is the MailOnline showbiz section,” Schofield says, holding up Willoughby’s smartphone. “The story that we told at the beginning of the show has now turned into the headline: ‘My whole bum was out’.”

“You didn't run around Downing Street like that did you?” Phillip laughed. “No it was just my knickers. In the toilet,” revealing that the zip break actually happened while she was in relative privacy. “It went completely.”

“I gave my coat in when my husband Dan and I arrived and you have to give your phone in as well. So I'm in the toilet with no coat, no phone, on my own, with my whole bum out! I had to wait for someone to come and say, 'Can you find my husband please? He's waiting outside the men's'."

She then had to explain to the Prime Minister's wife, Samantha Cameron, the host of the event, why she was wearing her coat the whole of the rest of the evening. "Of course, Dan found it hilarious. The staff were recommending gaffer tape and safety pins but I had to keep my coat on all night.”

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