Facebook stated Tess Holliday's photo depicted "body parts in an undesirable manner" Reuters

Facebook was forced to apologise after rejecting an advertisement that featured a plus-sized model. The social media network claimed that the image, which showed model Tess Holliday in a bikini, depicted "body parts in an undesirable manner" and thus violated its ad standards.

The advertisement was posted by the Australian feminist talk show group Cherchez La Femme, to promote an event titled Feminism and Fat, to promote body positivity. However, the post was denied for apparently contradicting Facebook's Health and Fitness policy.

Facebook wrote: "Ads may not depict a state of health or body weight as being perfect or extremely undesirable. Ads like these are not allowed since they make viewers feel bad about themselves. Instead, we recommend using an image of a relevant activity, such as running or riding a bike."

Cherchez La Femme shared Facebook's reply on their page and wrote: "We're raging pretty hard over here - both because Facebook seemingly has no idea that plus sized, self describing fat women can feel great about themselves, and also because we haven't been able to boost the original damn post."

Following the backlash, Facebook apologised for the incident. The company said in a statement: "Our team processes millions of advertising images each week, and in some instances we incorrectly prohibit ads. This image does not violate our ad policies. We apologize for the error and have let the advertiser know we are approving their ad."