Manchester United risk being priced out of a move for Luke Shaw after new Southampton manager Ronald Koeman reportedly raised his valuation by £10m.
The England international left-back was expected to make a switch to Old Trafford after the World Cup as part of Louis van Gaal's summer spending spree.
Reports have claimed that United lodged a £30m offer for Shaw prior to him travelling to Brazil with the Three Lions, but the Saints have since appointed Koeman as successor to the departed Mauricio Pochettino.
The Daily Mail understands that Koeman is desperate to keep hold of the 18-year-old and so will demand that the Red Devils raise their bid to £40m in order to sanction his sale.
Shaw is poised to make his England World Cup debut against Costa Rica on Tuesday.