Red Devils boss Mourinho wants two more signings before tomorrowâ€™s 5pm transfer deadline.
And according to Axel Witselâ€™s advisor Paul Stefani, Kante tops Mourinhoâ€™s wishlist.
Stefani claims United were interest in Witsel, who quit Tianjin Quanjian for Borussia Dortmund this week.
However, Witsel opted to join the Bundesliga giants after discovering Chelsea star Kante was Mourinhoâ€™s top target.
â€śThere were other candidates.Â Manchester United wanted him [Witsel], Napoli too,â€ť Stefani told Het Laatste Nieuws.
â€śBut I have told Axel: ‘At Dortmund you are the number one, at Manchester you are one of manyâ€¦ and at Napoli tooâ€™.
â€śI know from a very good source that Mourinho said he wanted Witsel, but not in the first place.Â Nâ€™Golo Kante topped his list.
â€śEventually Axel said: ‘Do me a favour and finish it as quickly as possible, because I really want to go to Dortmundâ€™.â€ť
Mourinho tried to sign Kante during his time at Leicester, just before Chelsea completed a deal for the France international, 27.
â€śIt was amazing to have Mourinho call me, even though Iâ€™d been warned before how he would appeal to me,â€ť said Kante.
â€śI listened to his arguments about why I should move to United but at that time I was hesitant between staying at Leicester or leaving for Chelsea.â€ť
Mourinho cut a frustrated figure during Unitedâ€™s pre-season tour of America.
The United boss has been vocal on his summer transfer plans, revealing heâ€™s far from happy with the Old Trafford board.
â€śWe basically have the same players,â€ť said Mourinho.
â€śThe players we have bought, one is a goalkeeper cover, one is a 19-year-old kid, so in fact we have one new player which is Fred.
â€śSo of course our team is not going to be very different.â€ť
Mourinho is desperate to splash the cash this summer to catch Manchester City this season.
United watched on last time out as Pep Guardiolaâ€™s side stormed to the Premier League title, with City breaking the 100-point barrier for the first time.
Man Utd transfer news – who has Jose Mourinho signed this summer?
Players in:Â Fred (ÂŁ47m, Shakhtar Donetsk), Diogo Dalot (ÂŁ19m, Porto), Lee Grant (ÂŁ1.5m, Stoke).
Players out:Â Dean Henderson (loan, Sheffield United), Joe Riley (undisclosed, Bradford), Sam Johnstone (ÂŁ6.5m, West Brom), Daley Blind (ÂŁ14.1m, Ajax), Matty Willock (loan, St Mirren), Cameron Borthwick-Jackson (loan, Scunthorpe), Max Johnstone, Jake Kenyon, Ilias Moutha-Sebtaoui, Devonte Redmond, Theo Richardson, Charlie Scott (all released), Michael Carrick (retired).