The tall 27-year-old Romanian international has also been linked with Cesena and Novara.
"We are in negotiations and Lazio like the lad very much," agent Ivan Reggiani told lalaziosiamonoi.
"He is fascinated by the chance to play alongside his fellow countryman, Stefan Radu. The Biancocelesti remain our priority and we've been in talks with them for over a month.
"We are at an advanced stage and Tamas is very likely to wear the Lazio shirt next season. The only doubts are around his behaviour.
"President Claudio Lotito and director Igli Tare are considering this aspect, but I can assure them Tamas is an exemplary professional. He's always the first to arrive at training and the last to leave."