The 85-year-old designer - who is the creative director of French luxury fashion house Chanel, Italian fur and leather goods fashion house Fendi as well as his own brand - has asked his long-time friend to become his new design partner.
To launch the partnership, the pair is set to reveal a collection of essential pieces in September called 'The Edit by Carine Roitfeld' which will include pieces from designer's autumn/winter 2019 line.
In a statement, Karl said: ''[Roitfeld] knows what she wants; she has a vision and she states her vision. She is actually what she seems to be; she matches her image, she fits in her universe, and she is a perfect match for KL.''
Carine added: ''[Lagerfeld] is one of the smartest, most inventive and innovative people I have ever known, after all these years, Karl never calls me Carine - always Madame Roitfeld.''
This news comes after the iconic designer was too ''tired'' to take his bow at the end of Chanel's haute couture shows earlier this month.
Karl missed both his fashion house's presentations in Paris with the studio's director Virginie Viard - a long-time friend and collaborator of the creative director - representing him on stage instead.
In a statement, Chanel said: ''For the traditional greeting at the end of the show, Mr. Lagerfeld, artistic director of Chanel, who was feeling tired, asked Virginie Viard, director of the creative studio of the house, to represent him and greet the guests alongside the bride. Virginie Viard as creative studio director and Eric Pfrunder as Chanel's director of image continue to work with him and follow through with the brand's collections and image campaigns.''
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