The Daily Mirror is reporting that West Ham United are determined to keep hold of the Austria international this summer and have placed a mammoth price-tag on him to ward off interest from interested clubs.
Manchester United have been strongly linked with a move to sign the 29-year-old in recent weeks after his impressive performances for the Hammers last season.
According to the same report, the east London club are bracing themselves for a bid from Manchester United for Arnautovic this summer but they are not prepared to let him leave on the cheap.
The speculation linking Manchester United with a move for Arnautovic heightened after Mourinho was pictured watching him in action during Austria’s friendly against Russia last week.
Manchester United have already begun their summer recruitment drive, with the Red Devils having wrapped up deals to sign Fred and Diogo Dalot last week.
The Red Devils are thought to be on the lookout for a number of other signings as they aim to challenge for the Premier League title next season.
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