Tim Gunn and Heidi Klum are leaving “Project Runway.” Amazon Prime Video on Friday announced the supermodel and fashion consultant are helping to develop a new reality fashion series, which will combine content with commerce. (AP Photo/Richard Drew, file)

Model Heidi Klum and American fashion consultant Tim Gunn, the stars who turned "Project Runway" into one of the first and biggest cable reality TV hits of the previous decade, are saying goodbye to the series and making the leap to streaming.

They have signed a deal to develop a new fashion-oriented reality show for Amazon Studios, reports variety.com.

Details of the new programme are not yet known, and no producers are yet attached, but sources say that Amazon will open a competitive process for production companies to vie to oversee the new show.

Klum and Gunn's Amazon deal throws into question the future of "Project Runway", whose season-16 finale aired last year on cable channel Lifetime. 

Bravo, the show's original network home, made a surprise announcement in May that the series would return to the NBCUniversal-owned channel for its next season with longtime production company Magical Elves again on board.

"After 16 incredible seasons, I am saying ‘Auf Wiedersehen' to ‘Project Runway,' a show that I was honoured to host and help create," said Klum

She added: "I am incredibly proud of the show, and it will always have a special place in my heart. I am so appreciative of the dedicated fans, and most of all, I am grateful that we could shine a light on creativity and help launch so many talented designers' careers. I'm most excited that my journey with my dear friend and colleague, Tim Gunn, is far from over. We will be partnering with Amazon for a new show, and we're excited for everyone to see what we're designing next!"
The deal with Klum and Gunn is the most recent with high-profile talent for Amazon under Jenifer Salke, the former NBC executive who became head of the tech giant's'entertainment division earlier this year. 

Amazon has in recent months set deals with Nicole Kidman, Jordan Peele and Barry Jenkins.