Napoli president Aurelio de Laurentiis says Marek Hamsik and Ezequiel Lavezzi are not for sale.
Manchester United are chasing Hamsik, while Lavezzi has been linked with Liverpool.
"Hamsik is unsellable. I have said it before and I repeat it again. The club's growth in strength passes through the establishment of young talents," De Laurentiis said.
"Hamsik is very important to our project and the argument is the same for Lavezzi. They are the legacy of this club. My dream is to have a team with 18 players of the highest level who are indissolubly linked to the blue shirt.
"We will win with this mentality and this maturity. With Lavezzi there can be a language problem, in the sense that we come from different cultures. But with Lavezzi we have recovered a good relationship."