Singer Johnny Hallyday denied rumours he is at odds with his producer, Jean-Claude Camus, and added he is outraged by the speculation.
The allegations are published in a book about the author, Johnny, les 100 jours où tout a basculé (Johnny, 100 days when everything changed), written by journalists Renaud Revel and Catherine Rambert.
Hallyday went on his web page on the Camus Productions website to leave a message for his producer.
It reads: "My dear Jean-Claude. Please know that I am shocked by the negative things I have read or heard about you and I. We have worked together for 34 years and I hope other artists get the chance to work with someone like you some day. Know that I trust you and send you lots of love. Your friend, Johnny Hallyday."
Johnny Hallyday had some rough times in 2009. He was hospitalized in Los Angeles on December 7 to receive treatment for a post-surgery infection. He spent 16 days in hospital and was put in a coma before finally checking out in better health. His concert tour in France last January was cancelled.
The 66-year old star was the victim of a medical error and finally lodged a complaint against Stéphane Delajoux, the doctor that performed surgery for a herniated disc in Paris on November 26, 2009.