It is believed the deal has all but been agreed, despite current kit manufacturers Nike still having the right to match any offer.
Nike’s deal with United dates make to 2002 and is set to expire in June 2015, although they are yet to decide whether they are prepared to more than double their current deal, which was worth £300m over 10 years.
Nike and United have been locked in negotiations for the last three years but, the brand’s exclusive negotiating period expired last year, paving the way for adidas to try and get a piece of the action at Old Trafford.
United officials reportedly met with adidas executives in Germany following their Champions League tie with Bayern Munich last month and it’s being reported that the biggest football club kit deal in history has almost been signed off by adidas.
United’s last deal with adidas was between 1980 and 1992.