The Italy international has been linked with Juventus, though the price-tag has been set at 30m.
"There have already been two or three offers, but so far the Biancocelesti have resisted," agent Federico Pastorello told Sky Sport Italia.
"He has ambitions and that is normal, as he'd like to play in the Champions League, but he never said that he wanted to leave Lazio.
"How much is President Claudio Lotito asking for? At least 30m, which is a lot of money, perhaps because he wants to say the player is not for sale.
"Currently Lotito is resisting all offers, but we'll see what happens in future."
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