The Serie A outfit have been heavily linked with the highly-rated centre-half for some time.
Speculation over recent weeks has suggested that an offer has been tabled for the talented 24-year-old.
Vasco, however, insist no transfer talks have been held, with Milan's supposed interest little more than gossip at present.
Club president Roberto Dinamite told Milannews.it: "I read about Milan's offer but this is just news, it's not concrete fact.
"Nothing official has come to us and without that we can't open negotiations."
He added: "There is a price and we will have to see if Milan want to reach that value. I can't speculate on that, you will have to speak with them.
"Of course the player likes Milan. The club is enticing.
"He could play in Italy and has a lot of potential. He is a national team player and could contribute a lot. Let's see if we receive any offers, and whether they interest both Vasco and the player."