Gremio chief Onore Luiz Meira admits defender Rever could be sold in January.
Lazio sporting director Igli Tare is in Brazil this week and has been linked with a move for the young Gremio fullback.
Meira said: "The negotiations are open. They have not yet submitted a formal offer, but Lazio is preparing a proposal. It is important to know what there intentions are and the needs of the Italian club, because for us Rever has a crucial value that deserves equal pay.
"But apart from the value to be recognized, there is also the need to evaluate the form of payment."