By William Oyo-Ita 5 Febuary 2016
The 53-year-old Portuguese, who was sacked by the Blues in December, is increasingly hopeful of succeeding Louis van Gaal at Old Trafford.
No agreement has been reached, and the club have made no comment, but negotiations have begun.
Dutchman Van Gaal, 64, is expected to leave United at the end of the season – one year earlier than scheduled.
That would leave the way clear for Mourinho, who is known to be excited by the prospect of taking over at Old Trafford.
