Senegal defender Kalidou Koulibaly is refusing to sign a new deal at Napoli

Chelsea have made a new £38m bid for Napoli defender Kalidou Koulibaly, according to Sky Italy.

The 25-year-old Senegal international is wanted by new Blues boss Antonio Conte to strengthen his defensive options, but Napoli are yet to respond to their offer.

Koulibaly's agent Bruno Satin confirmed earlier this week that Chelsea want his client, who is also refusing to sign a new deal with the Serie A club.

"Chelsea still want him and there's time to close the deal," Satin said. "We've decided to leave for economic reasons. After what happened to Higuain, though, Kalidou will not be leaving for Juventus or another competitor."

Koulibaly, who joined Napoli from Genk in 2014, is currently contracted at the Stadio San Paolo until the summer of 2019.

He has made 60 appearances in Serie A and played 19 times in Europe, scoring once for Napoli, and he has six caps for Senegal having represented France at U20 level.

Should he move to Stamford Bridge he will become Conte's third signing of the summer alongside striker Michy Batshuayi and midfielder N'Golo Kante.