
She released an inflatable pool float in the shape of her peachy rear, just in time for summer.

But Kim Kardashian, 36, proved there's nothing like the real thing on Sunday, as she proudly paraded her bulbous behind in a skimpy bikini during a holiday in Mexico with sister Kourtney, 38, and assistant Stephanie Sheppard.

After complaining that her friends were 'fat-shaming' her over unairbrushed pictures of her hourglass figure, Kanye West's wife Kim did what any body-confident beach babe would do and slipped on a thong, sticking a metaphorical middle figure up to the haters.

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Kimoj-eez! Kim Kardashian exposed her sizable behind in a thong bikini on Sunday, as she took off for a vacation in Mexico with sister Kourtney Kardashian and friends this week

Cheeky: From all angles, slim Kim was a perfect hourglass with her tiny waist somewhat disproportionate to her behind

Selfie queen Kim, who collated a best-selling book of her favourite shots of herself, is partial to a belfie post on Instagram but the new bikini pictures of her expose an un-retouched side of the stunning Keeping Up With The Kardashians star, which has won her high praise among fans.

Her distinctive rear recently featured in Kim's latest drop of Kimoji - personalised 'Kim' emojis - merchandise, being sold as a simple image of her bottom and hips on an inflatable pool float.

In the new holiday pictures, a smiling Kim was seen soaking up the sun in nothing but skimpy L*Space bottoms and a ripped crop top that knotted at her remarkably small waist.

Her recent weight loss - for which she controversially thanked a sickly 'flu' bug - struck a stark contrast between her toned middle and her shapely hips and bottom.

But slim Kim, now a mother of two, seemed quite delighted with the outcome and walked around looking carefree with bare feet and wet hair on her sunny vacation.

Cool at the pool: Kim's recent weight loss created a stark contrast between her narrow middle and her shapely thighs

‹ Slide me › Cheeky: The pictures finally expose an unairbrushed side to Kim's famous bottom (left, in October 2013 and right, on Sunday), and fans have been praising how enviable she looks

Here come the girls: Kim (left) is currently holidaying with older sister Kourtney Kardashian (right) and Stephanie Shepard (centre)

Bikini babes: It was a girls only weekend that also saw attendance from Larsa Pippen, Brittny Gastineau, Malika Haqq and Hrush Achemyan.

Mood: Kim was in especially high spirits, despite taking to Twitter to complain about her friends 'fat shaming' her

Rear of the year: The brunette has one of the most enviable bodies in showbusiness

Break the internet: Kim's perfect bum almost broke the internet in 2014, with her bare bottom Paper magazine cover

Even so, confident Kourtney ran rings around the girl group, showing that her own perky assets completely defied gravity as she performed cartwheels on the lawn.

Mother-of-three Kourt recently turned 38, but you wouldn't know it, thanks to her playful nature that showed she was still young at heart.

Kourtney similarly favoured thong bikini bottoms worn with a sporty cropped bikini top that needed no support for her age-defying bust.

Kim found the antics especially amusing, taking to Twitter to point out that 'naked cartwheels' were just one of the hilarious larks on the girls' Mexican getaway, which also featured Kourtney throwing up in her own bed.

The girls' weekend has welcomed all of the familiar faces into the fold, including Larsa Pippen, Brittny Gastineau, Malika Haqq and Hrush Achemyan - all playfully dubbed 'The Calabasas mom crew,' by Kim.

Kim provided a 'play-by-play' for fans, tweeting about the getaway as she, Kourtney and their friends spent some well-deserved time away from their children.

In shape: Having recently celebrated her 38th birthday, mum-of-three Kourtney looked to be in incredible shape

Stunning: Kourtney adjusted her swimsuit, prepping herself for some impromptu gymnastics

Cheeky: Kourtney was proving she's still young at heart as she performed cartwheels on the lawn

Joker: Young at heart Kourtney let it all hang out as she mimicked her kids with some frivolous gymnastics

Young at heart: Kourtney ran rings around the group, showing that her perky assets completely defied gravity

Cheeky: Kim recently monetised her distinctive behind, by making a pool float out of her hilarious bum Kimoji

Kim is mother to North, three, and one-year-old Saint West by husband Kanye, while Kourtney has Mason, seven, Penelope, four, and two-year-old Reign with estranged partner Scott Disick.

Body-conscious Kim recently celebrated escalating her post-baby weight loss when she contracted the flu, tweeting about the weight loss in an arguably 'irresponsible' fashion, after making a full recovery.

'The flu can be an amazing diet. So happy it came in time for the Met [Gala] lol #6lbsdown,' she wrote, praising her preparation for the Costume Institute Gala, due to be held this May in New York City.

Her friends have even been helping her to stave off the weight during the wild weekend, with Kim complaining that her milkshake was 'spiked' by her hair stylist Jen Atkin to stop her from consuming the calories.

Selfie-obsessed: Kim is known for sharing belfie posts of her bodacious behind (left, in October 2013) but the new holiday shots (right, on Sunday) have earned Kim high praise for showing off her real side

Joking around: Kim has been keeping fans up to date with the wild weekend, including accusations that Kourtney had been sick in her bed

Hose down: Kourtney cooled down with a refreshing outdoor shower by the pool

Busy mum: Kourtney has Mason, seven, Penelope, four, and two-year-old Reign with estranged partner Scott Disick

Natural beauty: Kourtney seemed to be wearing a very minimal coverage of make-up, including waterproof mascara

Yummy mummy: Kourtney and her mum friends have certainly been letting her hair down

Ouch: On Monday night, the 36-year-old star took to Twitter to post about gal pal Jen Atkin 'fat shaming' her, as she gave a play-by-play of the events of their girls' weekend

Flipping amazing: Perhaps Kim gave the reasoning for Kourtney's vomiting

Party hard: The middle Kardashian sister documented the 39-year-old antics

As for me? Kim claimed to be acting as good as gold, even cheekily referencing the hysteria over her unairbrushed photos by saying she looked 'flawless'

'@Jenatkinhair spiked my Oreo shake to try to get me to not eat it because she's fat shaming me,' Kim wrote, joking with her long-term friend in view of her 51.2M followers.

Afterwards, she hinted at the bikini pictures that have taken the web by storm this week - threatening once again to 'break the internet' as she so famously did in 2014 with her bare bottom displayed on the cover of Paper magazine.

Concluding her live tweets about the raucous holiday, Kim slyly tweeted: 'Oh and as for me you ask? ...I'm just sitting here on the beach with my flawless body.'

Twinning: Kourtney and her friend Steph were enjoying twinning vibes in matching black bikinis

Vibes: Kim has dubbed the girl group of Kourtney's friends 'The Calabasas mom crew'

In shape: Their thong bikinis will no doubt be the coveted style of the season, following their endorsement

Body conscious: The trio have been keeping a check on each other's diets to make sure they don't overindulge, Kim says

Chatting away: Kim shares a strong bond with Kourtney's closest girlfriends, it seems

Kim tossed her bobbed hair back as she put on her sunglasses during their chat

Relaxing: The trio enjoyed some time relaxing on an outdoor bed in the sun

The perfect spot: It looked like a secluded spot, away from fellow holidaymakers