Manchester United have made a second bid for Mason Mount but Chelsea are holding out for a fee closer to their valuation, sources have told ESPN.

United have already had one offer of £40 million ($51m) knocked back but have returned with a second offer worth close to £50m ($64m). Chelsea's valuation is £70m ($89m), and negotiations between the two clubs are ongoing.

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Erik ten Hag is keen to land the England international to bolster his midfield and take some of the burden off Christian Eriksen, who made more than 40 appearances last season after joining on a free transfer from Brentford.

Mount has a year left on his contract at Stamford Bridge, and negotiations over a new deal have collapsed. Sources have told ESPN that the 24-year-old, who came through Chelsea's academy, is open to a move to Old Trafford.

United, according to sources, believe £50m is a fair fee that reflects that Mount could leave Chelsea for nothing in 12 months' time.

Other interest in Mount has also cooled after Liverpool signed Alexis Mac Allister from Brighton and Arsenal and Bayern Munich turned their attention to different targets.

Sources have told ESPN that United remain confident they can do a deal for Mount that would see him signed in time to join Ten Hag's squad for the preseason tour of the United States, which begins in New York on July 20.

However, club sources have told ESPN that United are reluctant to stretch to £70m and that the transfer will depend on Chelsea lowering their demands.

Already this summer, Chelsea have reduced their valuations of Mateo Kovacic and Kai Havertz to facilitate moves to Manchester City and Arsenal, respectively.