Sky Sports is reporting that the Red Devils are keen on a deal to bring the 22-year-old defender to Old Trafford this summer as Ole Gunnar Solskjaer looks to bolster his options at the back ahead of next season.
The same story says that Manchester United are willing to pay £45m and offer a player to sign the defender this summer.
However, it is claimed in the same article that West Ham are adamant that Diop is not for sale, and they would not even listen to offers of less than £60m.
The article goes on to explain that signing a new central defender is Manchester United’s top priority in the summer transfer window.
They have apparently been told by Napoli that Kalidou Koulibaly would cost about £100m and that Leicester value Harry Maguire at £80m.
The same story also says that Manchester United are keen to bring in a new right-back this summer to replace departing captain Antonio Valencia.
Manchester United endured a disappointing season last term as they ended up in second place and without a trophy.
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