The model came under fire today after making some rather harsh comments about Kelly's bikini body in her Sun column.
After thousands of unhappy responses from fans, Katie decided to settle the matter by backing up her words on Twitter this evening.
She tweeted: "I love the fact people comment on my opinions!everyone has nasty opinions to say about me I havent said anything untrue just my observation [sic]"
But that did nothing to stop the outrage pouring in from her followers, with one user replying: "'heffer' means a size comparable to a cow?! So that is your true observation? You're either mad or just spiteful!"
Katie initially claimed that mums should point their teenage daughters in the direction of Kelly for body inspiration, but managed to completely contradict herself by then calling Kelly a 'heffer'.
She wrote: "Every mum should make her daughter look at pictures that show Kelly modelling her latest New Look swimwear range in Miami.
"They don't seem to be air-brushed and I'm FLABbergasted to see how big Kelly really is ... You're a heffer, Kelly, but still a hot one."
[ Related article: Kelly Brook gets over her split from Thom Evans and those Danny rumours by getting her boobs and legs out ]
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She then proceeded to claim that Kelly had "probably been doing a bit of comfort eating" following her split from Thom Evans.
Despite the hoo-ha happening in her name, Kelly has remained tight-lipped on the situation and instead took the opportunity to promote her new spot on the Celebrity Juice panel.
She tweeted: "Just finished a Morning of interviews about Celeb Juice!!! Can't wait to start xxxx"
[ Read more: Katie Price labels Kelly Brook a 'heffer' after saying she looked 'big' in her bikini ]