The makers of upcoming Telugu-Tamil bilingual "Mahanati", a biopic on the late south Indian actress Savitri, are yet to officially sign any actor to play the leading role in the film, a source said."We are in talks with multiple actresses but nobody has been finalised yet. It might take a few more weeks before an official announcement will be made," a source from the film's unit told IANS.To be directed by Nag Ashwin, recent reports claimed Samantha Ruth Prabhu is among the actresses under consideration for the lead role."It's tough to pinpoint one actress at this moment because it's too early," the source said.The director also has plans to run an online poll to zero in on the suitable actress."We are planning to have some sort of poll. Savitri was a people's actress and she was owned by them. It will be nice to hear what people have to think about the project and see who they will recommend for the lead role. We want to make the whole process very interactive," Ashwin had earlier told IANS.