The Ukraine striker was on loan with the club last season but has returned to Liverpool where it is uncertain of just how much game time he will be involved in.
Hertha coach Lucien Favre and general manager Michael Preetz said they were both still interested in the 30-year old.
"Yes, I have contact with Andriy, just spoken to him on the telephone,” Favre told Bild.
"The contact was never broken off. He played excellently for us."
Preetz added: "We would like to have Voronin - if it was financially doable."