Justin and Hailey Bieber are threatening legal against a cosmetic surgeon over claims he made about the model

In the video, the surgeon showed two photos of Hailey at different points in time.

He said: "Pay special attention to the nose. What do you think?

"Well, I'll tell you what I think. I think it's physically impossible without getting a little bit of help from someone like myself to go from this picture to that picture."

Dr. Barrett also suggests Hailey has undergone a skin tightening procedure, jawline contouring, and genioplasty - a procedure to alter the shape of the chin - as well as hinting she's had fillers.

However, the Biebers - who have been married since 2018 - have now decided to fight back, with their attorneys accusing the surgeon of using her "name, image and likeness" to promote his practice.

What's more, Dr. Barrett has been accused by the celebrity duo of using "copyrighted protected lyrics" from Justin's hit single 'Sorry' in his TikTok video.

A section of the cease and desist letter reads: "These flagrant and conscious infringements of our Clients' rights constitute a number of violations including, without limitation: misappropriation of name, likeness, image and persona for commercial purposes, misrepresentation, defamation, slander, false light, violation of rights of publicity, copyright infringement, trademark and service mark infringement, unfair competition, dilution, and interference with our Clients' contractual obligations to third parties."

Dr. Barrett has been warned by the couple that he's subject to "statutory damages for each wilful infringement".

Justin and Hailey also want the surgeon to publicly retract his claims about the model.

Despite this, Dr. Barrett is standing by his accusations.

He told E! News: "The purpose of my TikTok account is to increase the transparency of plastic surgery and to educate people about plastic surgery.

"The purpose of the video was not to disparage Hailey Bieber in any way, the purpose of my video was to share my opinion about the procedures that I believed she may have had done based on photos alone.

"This is at the request of many of my viewers who follow me for this type of information and for my opinion."