Kendall Jenner struggles to hold her jeans as she steps out in $10,000 Saint Laurent crystal boots with her NBA 'boyfriend' Blake Griffin to celebrate her 22th birthday (Details, pics)

It's been claimed they are now an 'official' couple after months of dating.

And Kendall Jenner only fuelled speculation when she invited Blake Griffin to sit shoulder-to-shoulder with her nearest and dearest for her 22nd birthday dinner, which was held at West Hollywood's Petite Taqueria on Thursday night. Things certainly seem to be getting serious between the pair, as the basketball star was among a select few who were chosen to help celebrate Kendall's special day.

Rocking an outfit that wouldn't have looked out of place on her sister Kim Kardashian, supermodel Kendall showcased her taut torso in a cropped white vest.

She paired the minuscule number with a pair of ripped jeans that seemed to be in need of a belt to help cinch them up on the model's narrow waist.

Completing her attire was a pair of kinky knee-high boots covered in crystals, retailing at an eye-watering $10,000 at designer fashion house Saint Laurent, as she strode into the popular eatery.  Matching her casual style, Blake also sported a low-key look, donning a simple T-shirt beneath a checked shirt and jeans.

Despite sporting a loud ensemble, Kendall seemed to want to go under the radar when leaving the bash, no doubt because she was snapped leaving the restaurant in the company of her rumoured beau. While they made solo entrances into the eatery, their departure was more than cosy as they both clambered into the back of an awaiting car.

Uncharacteristically camera shy, Kendall attempted to conceal her face beneath her hand as she hoisted her legs up, placing them close to Blake's knee. It's been reported Kendall and Blake have decided to move beyond the hooking up stage onto something more serious.

A source told Us Weekly: 'They're legit. They're a full-on couple. 'Kendall has been going to a lot of his games and they have been enjoying time at home when Blake is in town. They're good.'

It was said she was both dabbling with with Blake while still talking to her rapper ex-boyfriend A$AP Rocky, who she enjoyed a brief affair with last year. The star's new relationship status comes just over a month since it was claimed she was enjoying 'playing the field.'

An insider told People last month: 'Kendall and Blake have been hanging out quite a bit and are having a good time. They met in passing a few times and hit it off.

'She's still talking to Rocky as well. But he isn't the type to settle down or be a good boyfriend, so she's playing the field too. She's seeing Blake romantically. It's nothing serious. She has been in LA a lot lately, and is having fun.'

The source added: 'Kendall is keeping her options open. She's still dating A$AP Rocky as well, but she and Blake are hanging out, and there's potential there.' 

Meanwhile, Kourtney Kardashian and her younger boyfriend Younes Benjima, as well as Kim Kardashian and her husband Kanye West, also turned out to join the runway staple for her pre-birthday meal. They were followed closely behind by matriarch Kris Jenner, who once again defied the years with her chic style.

The 'momager' opted for an all-black ensemble, comprised of a demure black dress and racy thigh-high boots.

The 61-year-old looked to have put her feuding with ex Caitlyn Jenner to one side for the evening, as they put on a united front to celebrate their daughter's birthday.

Caitlyn was pictured sporting a glamorous hair and make-up look as pulled up to the venue alongside a female companion.Opting to show off her famous curves, Kim donned a khaki bralet and grey maxi skirt, which clung to her figure.