Chef David Colcombe has left the two-AA-rosette Birmingham restaurant Opus to "pursue other interests".
Colcombe was chef-director of the Opus group, which comprises the city centre restaurant, Café Opus and the recently launched Bar Opus.
He has worked with fellow directors Ann Tonks and Irene Allen since the company's launch 10 years ago, and his exit has come as a surprise, according to the Birmingham Post.
All parties involved offered only a brief explanation for the chef's departure, but stressed that it was by "mutual agreement".
Colcombe said: "I have left Opus in mutual agreement and I will go on to pursue other interests."
A spokesman for Opus said: "David has moved on to do other things. He has left by mutual agreement."
Founded in 2005, Opus Restaurant has two AA-Rosettes, and serves high-end food in a smart yet casual setting. Café Opus is set within the Ikon Gallery in Birmingham, and focuses on British producers and classic café dishes, while Bar Opus was launched last November at Snow Hill.
Colcombe was appointed an honorary fellow and visiting professor at University College Birmingham in 2009.