Napoli are reportedly not prepared to lower their €110m (£96m) asking price for Kalidou Koulibaly.
The 28-year-old has been restricted to just 15 Serie A appearances this season due to injury but has again been in impressive form for his Italian club.
Manchester United and Real Madrid have recently been linked with the Senegal international, although Liverpool are believed to be at the head of the queue for the centre-back.
There have been suggestions that Napoli could lower their valuation of the defender during this summer's transfer window, but according to Il Mattino, the Serie A giants will demand €110m (£96m) before agreeing to sanction his departure ahead of the 2020-21 campaign.
Koulibaly, who has a contract with Gennaro Gattuso's side until the summer of 2023, started his professional career at Metz before joining Genk ahead of a switch to Naples.
Tottenham Hotspur and Manchester City have also been credited with an interest.
