Ruiz, who is expected to play a key role for La Roja at this summer’s European Championships, has been heavily linked with a move back to Spain in 2021.
The former Real Betis schemer has established himself as one of the top midfielders in Italy in recent seasons but he has stalled on a contract extension in Naples.
According to reports in Italy, as covered by Diario AS, Ruiz has now rejected two extension offers from the club and wants to leave.
If he continues to opt against a new deal, Napoli will look for a sale in the coming months, to avoid the potential of a long running free transfer battle or a reduced price in 2022.
Both Spanish sides are rumoured to be willing to pay in the region of €45m for the 25-year-old but Napoli are determined to stick to their €60m asking price this summer.