The lawyer for the French company at the heart of an escalating global breast implant scare told Reuters on Tuesday that most of the protheses sold by the firm since 1991 were produced using a non-approved silicone.

Lawyer Yves Haddad, who represents now-shuttered Poly Implant Prothese (PIP) and its founder Jean-Claude Mas, said the company sold both so-called "simple" protheses, made with non-approved silicone, and a high-end product using approved silicone that was aimed at wealthier clients.

"There is a product made by PIP which did not formally receive the (regulators') approval and in this regard there was a violation of regulations," Haddad told Reuters in an interview in his office.

No charges have been filed in the case but a court in Marseille is likely to announce fraud charges next year, legal sources have told Reuters. An involuntary homicide investigation was recently opened after the 2010 death of a French woman from cancer who had PIP implants.