Kelly Osbourne fans scream she's 'too thin' as star appears frail and gaunt at BRIT Awards

Kelly Osbourne's extremely thin appearance at The BRIT Awards on Saturday sparked concern on social media.

Fans described Kelly as looking 'gaunt' and 'frail,' with some even bluntly telling her to 'get help' amid her dramatic weight loss.

Kelly, 41, who made a heartfelt speech about her father Ozzy during the show with mother Sharon, 73, was dolled up in a clingy black velvet number with corseted waistline, plunging cleavage and fishtail train.

She arrived to the event wearing a black feather bolero jacket but later tossed it off, which only served to show how slim her frame really was.

Kelly's blunt-cut hairstyle accentuated the sharpness of her cheeks and jawline.

Family matriarch Sharon mirrored her daughter's gaunt pout while dressed in a tuxedo-style get-up with floor-length coat.

Both Kelly and her mother incited comments from social media followers, but it was the younger of the two who seemed to elicit the most responses.

'Oh Kelly I really hope you get some help,' one wrote, while another added, 'The way kelly looks is heartbreaking.'

'Kelly needs help. Badly. This is so freaking sad!' a third ventured to say.

'This is drastic and quite unsettling!' yet another vented.

One fan remarked that Kelly did 'not look healthy' and encouraged the star to 'get a nutritionist and put some meat on the bones.'

Kelly and her mother were at the event to honor Ozzy, who received a posthumous Lifetime Achievement Award with Robbie Williams leading the tribute to the heavy metal icon.

Earlier this week, the mother-of-one clapped back at online trolls who criticized her shrinking figure.

Kelly took to Instagram to share a screenshot of one message, which read: 'Looks like a dead body... she's too thin and fragile... looks like she's going to see her dad soon,' followed by a string of laughing emojis.

In response, Kelly wrote: 'Literally can't believe how disgusting some human beings are! No one deserves this sort of abuse!'

Sharing a second post, she added: 'This too shall pass, but like, holy f**k.'

Kelly has denied using weight loss medication, but her appearance at a string of public events has generated genuine concern for her health and well-being, including a front row sighting at London Fashion Week on February 22.

And the singer and TV personality looked drastically slimmer while attending Ascot Millinery Collective's catwalk presentation at Mayfair's Claridge's.

The constant criticism over her physical appearance has provoked Kelly to repeatedly defend herself following the sudden death of her father at his Buckinghamshire home last summer.

Over the years, the British fashion designer has admitted to insecurities about her weight, which dates back to her teen years while starring in her family's reality show, The Osbournes.

'I got pulled into the head of the agency's office and he … gave me a whole speech about how I was too fat for TV and I needed to lose weight, and that if I lost weight, I would look better,' she revealed on The Osbournes podcast last year.

'And he was just saying, 'You're not a movie star, but you could be one if you lost weight.' Osbourne's weight journey has been a rollercoaster ride ever since.

She underwent gastric sleeve surgery in 2018, calling it 'the best thing I have ever done,' and credited surgery, strict diet and high-intensity interval training for helping her to shed 85lbs.

Kelly tipped the scales again when she gained around 100lbs while pregnant with her son Sidney, now three, and developed gestational diabetes, later admitting she shunned the spotlight as a result.

She has time and time again fended off critics who scrutinize her dramatic transformation while attempting to squash persistent Ozempic rumors, previously telling Extra: 'I know everybody thinks I took Ozempic. I did not take Ozempic. I don't know where that came from. My mom took Ozempic.'