He said this in an interview with an Austrian TV channel, Censor.NET reports citing Ukrainski Novyny.
"Firtash is a witness, but not a defendant in the investigation, which has been carried out by the Austrian police in his house. Firtash has been filed no charges," the lawyer said.
He stressed that Firtash was cooperating with the Austrian judicial authorities.
Earlier, Ukraine's Ambassador to Austria Oleksandr Shcherba wrote on Twitter that a search was underway in Firtash's house in Vienna and suggested that new charges were filed against the businessman, allegedly by the German law enforcement authorities.