ESPN is reporting that the Red Devils are ready to wait until the end of the season to land the 27-year-old centre-half because Napoli are unlikely to let the player leave this month.
The same story says that Manchester United are keen on signing a new central defender this month, with Inter Milan’s Milan Skriniar, AC Milan’s Alessio Romagnoli and Leicester City’s Harry Maguire also on their radar.
According to the same report, Manchester United had been hoping to try and sign Koulibaly this month, but Napoli have so far refused to negotiate, and that is making a summer transfer look more likely.
The same article also quotes sources as saying that the defender would be open to a transfer to Old Trafford.
Koulibaly has made two assists in 18 Serie A games for Napoli so far this season.
According to the same story, Manchester United are still open to making reinforcements in the January transfer window, but they accept that it may be difficult to bring in the players they want.
Meanwhile, Manchester United are currently preparing for their crunch Premier League showdown against Tottenham Hotspur at Wembley on Sunday afternoon.
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