Manchester United will have to pay a huge fee to sign Napoli defender Kalidou Koulibaly, according to reports.

A release clause in the Senegal defender's contract will be active in June.

The bad news for United fans is that the clause is worth £127m, per Italian newspapers Corriere dello Sport and Corriere del Mezzogiorno.

PSG have also been linked with Koulibaly and have the financial clout to meet the release clause.

United are desperate to sign a world-class defender to pair alongside Harry Maguire, who they made the world's most expensive defender last summer.

Napoli could be forced to sell Koulibaly as they look unlikely to qualify for Europe next season.