Napoli president Aurelio de Laurentiis wants to keep hold of Edinson Cavani and Marek Hamsik.
Both players have been linked with Chelsea and Manchester City this season.
"We had to pay a lot for him so anyone wanting Cavani will have to make an adequate offer. Not out of respect for me, but for him. He is a really good player who feels happy at Napoli.
"As for Hamsik, there have been many requests down the years but he has a contract with us until 2016.""Do clubs in England and Spain have the money to buy Cavani? We will see," De Laurentiis told Sky Italia. "We have recently spent a lot of money on (Eduardo) Vargas and we are waiting for him to grow as a player.