Koulibaly has been linked with a move to the Premier League, Napoli’s price has been slowing down Senegal’s international bid.
However, their failure to qualify for next season’s UEFA Champions League has opened the door to reducing bids considered acceptable in the summer window.
According to Gazetta Dello Sport, Manchester United are the most likely United clubs to make a significant effort to sign a 30-year-old player later this month.
Napoli president Aurelio de Laurentiis is reportedly still seeking to recoup at least £ 45million from Koulibaly, a sharp drop in his estimate after more than £ 80million.
Koulibaly has 2 years left on current his contract, putting Napoli in a position where they will have to be open to agreeing with any interested clubs.