Hamsik, 24, is being chased by a number of top European sides and has continued his good form this season with seven goals in 22 games.
The Slovakian’s agent, Mino Raiola, said: “If Napoli were to receive an offer from Barcelona, Chelsea or Real Madrid, then it would be logical to accept.”
Chelsea boss Andre Villas-Boas will be keen to boost his squad this month with his side’s title challenge wilting.