MANCHESTER UNITED have failed in their bid to sign West Ham United defender Issa Diop, according to reports. An offer amounting to £45million and a player was not enough to convince the Hammers to sell their star centre-back. French TV network TF1 carry the news but have not named the Red Devil involved in the proposed player-plus-cash deal. Diop only joined West Ham last summer but the 22-year-old developed excellently during the campaign as the club finished tenth.Making 38 appearances across all competitions, the Frenchman is reportedly valued at £60m by his current team. The Hammers forked out a club-record £22m when signing him from Ligue 1 club Toulouse. Such demands are not unlike the other major signings United are linked with making this summer. Leicester City star Harry Maguire is valued closer to £80m and Kalidou Koulibaly, a favourite at Napoli, has a similar price tag.But the potential exits of Paul Pogba and Romelu Lukaku could raise enough funds for the Old Trafford outfit to meet those demands. Latest United NewsBRIGHT IDEA Solskjaer challenges Man Utd to demolish Brighton too after Partizan rout MAN UTD 3 PARTIZAN 0 Greenwood, Martial and Rashford shine as United find shooting boots ‘SPECIAL’…