Manchester United slap £5million price-tag on goalkeeper Sam Johnstone who could leave the Red Devils in the January transfer window

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Manchester United have put a £5million asking price on goalkeeper Sam Johnstone who is currently on loan at Aston Villa but could be sold by Jose Mourinho in the January transfer window.

West Ham, West Brom and Crystal Palace have all watched 24-year-old Johnstone impress for Villa this season and the Championship club are worried their No1 will be snatched away if a Premier League side match United's valuation.

Villa, whose manager is former United captain Steve Bruce, would love to sign Johnstone on a permanent basis themselves but have to sell-to-buy as they are close to falling foul of financial fairplay regulations.

Manchester United have put a £5million price-tag on goalkeeper Sam Johnstone

It means Bruce could be willing to listen to offers for midfielder Henri Lansbury to raise funds with his options limited elsewhere.

Prize asset Jack Grealish needs to play more football after missing most of the first half of the season through injury while Villa still owe Brentford instalments for striker Scott Hogan which would eat into any transfer fee they would receive.

Johnstone has 18 months left on his contract at United which means this window would be the best financial time to cash in.

The 24-year-old is on loan at Championship side Aston Villa but could be sold in January

Bruce revealed last week that Villa fan Prince William had recently urged him to try and get Johnstone signed up full-time.

It remains to be seen whether a top-flight club decide to splash out on Johnsone next month. West Brom are looking to provide competition for Ben Foster but manager Alan Pardew would like to strengthen in other areas too.

West Ham only have Joe Hart until the end of the season while Palace are looking for two goalkeepers with 38-year-old Julian Speroni nearing the end of his career and Wayne Hennessey out of contract at the end of the season.