Neither Monaco nor Inter Milan are close to matching Lazio's valuation of Keita Balde, sporting director Igli Tare has said.
Balde, 22, has been linked strongly linked with a move this summer, with Juventus having had an offer rejected.
Monaco are reported to be close to selling Kylian Mbappe to Paris Saint-Germain, and could yet offer the kind of sum Lazio want.
But Tare told Mediaset: "Not only Monaco are interested -- there are other clubs after him, too -- but they are a long way off meeting our demands.
"He has a contract until 2018 with Lazio, and we are insisting on [the right fee] because he was brought up here and it's only right that the price reflects what he is worth.
"I don't know, in the end, if he will remain with us -- it's hard to give an answer right now. We'll see what happens between now and Aug. 31."
Lazio are reported to be demanding more than €30m for the winger -- far less than the €100m they would have to pay for Torino's Andrea Belotti, another of their targets should Mbappe leave.
His stunning overhead kick against Sassuolo at the weekend "explains why he is worth €100m," coach Sinisa Mihajlovic said, while the Turin club's sporting director Gianluca Petrachi added that if such an offer were to arrive Belotti would have the final say.
"Certainly it would put us in a position where we could not say yes or no," he told RAI.
"It would then be up to the player to decide. For now, no offer has arrived which has made us think.
"He's a great, humble lad and a player that any club would like to have in their squad."