With Louis van Gaal’s future at Old Trafford hanging by a thread, United have been linked with ex-Chelsea chief Mourinho for several weeks.
Now Football Insider claim a ‘pre-contract agreement’ has been signed by the Special One.
They report that the 53-year-old will pocket £16m-a-year, or £308,000-a-week, in a three-year deal.
Football Insider go on to say that Mourinho ‘has landed the job of his dreams’ following lengthy negotiations that have rumbled on for over six weeks.
It is understood that Van Gaal will stay in charge for the rest of the season but then be removed one year before his contract was due to expire.
Mourinho, sacked by Chelsea in mid-December, will then be appointed and oversee the club’s summer transfer business.
United’s troubles deepened last night after they lost 2-1 to Danish minnows FC Midtjylland in the Europa League.
Van Gaal’s men face a huge task to get into the top four this season and looking highly likely to miss out on Champions League football next season.
United, without captain Wayne Rooney who is sidelined with a knee injury, face a tricky trip to Shrewsbury in the FA Cup on Monday before hosting Arsenal in the league the following weekend.
After last night’s defeat, under-fire Van Gaal thanked the United fans for their support during the club’s tough period.
He said: “It is disappointing for them like we are disappointed.
“I am very grateful for the fans who supported us but we wanted to win and now we have to win at Old Trafford and then we are in the next round.
“We have to do it, it will not be easy but we have to do it.”