The 24-year-old, who joined Man United in 2009 but has never featured for the first team, joined Villa on loan in January 2017.
Steve Bruce has spoken highly of Johnstone in the past and wants to secure his services permanently following a superb second campaign at Villa Park, with the Birmingham side currently third in the Championship.
And according to the Sun‘s Daniel Cutts, United will take advantage of Bruce’s admiration for Johnstone by placing a £6.5m price tag on his head.
The Englishman has spoken of a desire to remain at Villa to play regular first team football, and you can be sure of him pledging his long term future to the club should they earn promotion back to the Premier League for next season.
And with David de Gea recently reminding everyone of why he is the best in the world against Sevilla and Crystal Palace, along with Sergio Romero – one of the better second choice keepers around – staying put over the January transfer window, you struggle to see the appeal of going back to Old Trafford at this moment in time.