Napoli made a bid for in-demand Inter Milan striker Mauro Icardi during the January transfer window.
The forward has scored 18 goals for his club this season and has attracted interest from Real Madrid, Arsenal and Manchester United.
But it was Serie A leaders Napoli who made the first move last month.
President Aurelio de Laurentiis told AS: "Icardi will score 40 a season here under (manager Maurizio) Sarri and can become like Cristiano Ronaldo.
"I tried to negotiate signing him with his wife, who is an attractive and charming woman. I offered €55million. He is a champion. Will they sell to Napoli? Why not? Never say never."
Arsenal's interest is likely to wane after the arrival of Pierre-Emerick Aubameyang for £56m while United signed Alexis Sanchez from the Gunners.
But Real are almost certain to sign a new striker in the summer given their struggles in front of goal this campaign.