Not safe for work! Zac Posen grabs Heidi Klum's bare breasts in topless Instagram snap as they promote Project Runway

By Mail Online Reporter

They have forged a close friendship working as fellow judges on Project Runway.

And Heidi Klum showed just how intimate she and Zac Posen have become - as she posed topless, with his hand over her bare breast for an Instagram snap.

The 41-year-old supermodel shared the image on Instagram on Thursday, just hours before their hit Lifetime reality competition series was set to air. 

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'I need something to wear for tonight's Project Runway': Heidi Klum posted this racy Instagram photo in which producer and judge Zac Posen has his hand over her bare breast

'I need something to wear for tonight's Project Runway': Heidi Klum posted this racy Instagram photo in which producer and judge Zac Posen has his hand over her bare breast

Wearing nothing but a petite pair of pink briefs, Heidi once again made it clear that she is very comfortable in just her own skin.

The German born beauty's long tanned legs and washboard stomach were on display as she stretched herself out and flung an arm in the air with her head of blonde hair tossed backwards.

Designer Zac pulled a cheeky face as he gripped the blonde around the waist.

More toplessness: Heidi is currently dating 27-year-old art enthusiast Vito Schnabel, and the pair were seen frolicking topless together at a beach in Tulum, Mexico, in April

More toplessness: Heidi is currently dating 27-year-old art enthusiast Vito Schnabel, and the pair were seen frolicking topless together at a beach in Tulum, Mexico, in April

His left hand saved Heidi's modesty in the otherwise racy snap.

'I need something to wear for tonight's @projectrunway,' she complained.

Heidi - who has daughters Leni, 10, and Lou, four, plus sons Henry, eight, and Johan, seven - seemed to take no issue with the idea of presenting this photo to the public.

And it's not the first time she has shared her topless body with the internet, either.

'Smile!' back in 2013, the supermodel and mother posted yet another topless snap, this time up close and personal... with a cheeky smiley face on her abs as she lay on a Bora Bora beach

'Smile!' back in 2013, the supermodel and mother posted yet another topless snap, this time up close and personal... with a cheeky smiley face on her abs as she lay on a Bora Bora beach

The America's Got Talent judge has developed quite a reputation for herself when it comes to posting Instagram photos that toe the line of appropriate.

She has decorated her social media profile with images of herself sunbathing with nothing up top, plus another of her cuddling a Bora Bora palm tree.

Heidi, whose career has largely involved quick changes in and out of different outfits in rooms full of stylists and design crew, revealed in a 2010 interview with Tatler magazine that nudity is no big deal to her.

Heidi explained her breezy attitude towards having no clothes on, saying she 'grew up in a very easy-going family where [her] parents were always naked.'

Come here, palm tree! On the same trip to Bora Bora, Heidi shared this one without a top yet again

Come here, palm tree! On the same trip to Bora Bora, Heidi shared this one without a top yet again

Completely comfortable with nudity: Heidi tweeted this topless sunbathing snap in December 2012, after explaining in an interview in 2010 that she has no qualms being nude around her family

Completely comfortable with nudity: Heidi tweeted this topless sunbathing snap in December 2012, after explaining in an interview in 2010 that she has no qualms being nude around her family

'My parents are still naked. I mean, it’s not like we’re hippies and we run around naked, but if they happened to be in their room changing or something or someone comes out of the shower, they’re not, like, 'Oh my God. No. Close the door.'' she went on.

Heidi, who was married to Seal at the time of the interview, said that her children 'see their parents naked all the time. We are not ashamed.'

The bold bombshell is currently dating 27-year-old art enthusiast Vito Schnabel, and the pair were seen frolicking topless together at a beach in Tulum, Mexico, in April.

Seal, meanwhile, has recently been pictured smooching a new blonde beauty as he moves on from their seven-year marriage.

Happy couple: Heidi Klum, 41, posted a photo with her 28-year-old toy boy Vito Schnabel on the model's Instagram account on Monday

Happy couple: Heidi Klum, 41, posted a photo with her 28-year-old toy boy Vito Schnabel on the model's Instagram account on Monday

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