Vidic has just enjoyed the best season of his career in terms of personal performance and is a pivotal part of United's defensive strength in partnership with Rio Ferdinand.
However, despite being settled on the pitch, the Serbian's wife has, according to a report in the Daily Mail newspaper, never become accustomed to the Manchester weather and craves a move to sunnier climes.
Barcelona and Milan both hope to exploit Vidic's situation and will table £25 million bids for the defender.
United will do all they can to resist such moves, with the 27-year-old seen as a key figure in United's attempts to win back the European Cup from Barcelona next season.
Vidic is more than happy to sign up to the United cause but marital pressures may yet come to bear on his decision making.
Meanwhile, United are prepared to let three of their young prospects leave the club and have placed them on the official transfer list.
Manager Sir Alex Ferguson has told Danny Simpson, Darron Gibson and Frazier Campbell that they are free to look for new clubs this summer.
The three all have Premier League experience and Ferguson will be hopeful of raising somewhere in the region of £10 million for their combined sales.
Hull City had a £7 million bid for Campbell, who spent much of last season on loan at Tottenham, rejected last year but with only a year left on his contract Phil Brown will be confident of getting him for less than that now.
Newcastle United and newly promoted Birmingham City will be interested in Simpson, who could be bought for as little as £1 million, while Gibson, who was impressive during United's Carling Cup run to the final last season, has already attracted the attentions of Wolves.