The centre-back had confessed he was not sure where he would be playing next season, as negotiations dragged on over a new deal.
His current contract is due to expire in June 2023 and Napoli were offering an extension only with a massive pay cut.
The club is trying to vastly reduce the wage bill overall, despite qualifying for the Champions League, and this has caused problems with several historically important players who feel disrespected.
Senegal international Koulibaly has been at Napoli since 2014 and has no shortage of suitors, including Barcelona, Juventus, Paris Saint-Germain, Chelsea and Manchester United.
He turns 31 later this month and has reportedly told his agent that he will not consider another Serie A club out of respect for the Partenopei.
The asking price on the market a couple of years ago was €100m, but with his contract situation and advancing age, that is now closer to €40m.
#Koulibaly, brutte notizie da Sky Sport. Massimo Ugolini:
“Non si è trovata l’intesa per il rinnovo, quindi o adesso o fra un anno Kalidou dirà addio al #Napoli. Pronto a fare una nuova esperienza in un altro top club. Ha 31 anni e il prossimo è l’ultimo contratto importante”. pic.twitter.com/XgDu58dDLr
— Manuel Guardasole ✍🏻 (@MGuardasole) June 9, 2022