Chelsea have made a £43 million bid to sign Napoli defender Kalidou Koulibaly, according to Il Messaggero.
The Blues previously had a £23m offer rejected for the 25-year-old, but have now raised the stakes in order to prise the centre-back away from the Serie A side.
Conte, who is facing something of a defensive crisis at Stamford Bridge, is determined to secure a deal for the Senegal centre-back this summer reports goal.com.
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