Bologna director Walter Sabatini insists Takehiro Tomiyasu will only be sold on their terms.
The defender is a target for Tottenham and Atalanta.
But Sabatini said Calciomercato.it: “It is only Bologna who can close a deal and we are not yet at that phase.
“Let it be clear, Tomiyasu will only move for the valuation that Bologna give him and not the one set by others, so it'll be very difficult to see him make a transfer."
Bologna have also been linked with Marko Arnautovic, who is trying to secure a release from his Shanghai SIPG contract.
Sabatini added: “We haven't signed Arnautovic yet, but it's early days in the transfer market, we'll see what happens over the next few weeks."