Goal can confirm that United are considering a move for Koulibaly ahead of the 2020-21 season, irrespective of whether Ole Gunnar Solskjaer is still manager at Old Trafford.
United have endured their worst start to a season in 30 years and are already eyeing up potential signings for next year, including 28-year-old Koulibaly and West Ham midfielder Declan Rice.
However, speaking at Senegal's training camp during the current international break, Koulibaly insisted he is only focused on winning matches with Napoli, distancing himself from the transfer speculation.
"I’m used to it," he stated in regards to the transfer talk. "So many [stories] come out each day, which say I’m leaving. Right now, my only objective is to win with Napoli. I don’t care about the rest.
"I haven’t made the best start to the season. Juventus remain the team to beat. For our part, we must work even harder, improving our game to get closer to them.
"We must think positively and be aware that we can do well. My objective is to help the club and team win a trophy now."
Koulibaly was previously linked with a move to United, with the hierarchy at the Red Devils viewing him as a suitable partner for Harry Maguire, who became the world's most expensive defender when he moved to Old Trafford from Leicester in the summer.
West Ham and England star Rice, meanwhile, is contracted until 2024, while potential moves for both players will not be affected by Solskjaer's future, with the Norwegian currently under pressure in the top job at the club.