Spanish media outlet Sport, as quoted by Metro, is reporting that the Red Devils have redoubled their efforts to sign the Netherlands international.
The same article states that Manchester United have improved upon the €14m-a-season (£12.3m-a-season) contract offer that the Red Devils made a couple of weeks ago.
According to the same story, the 20-time English champions are now the favourites to sign De Ligt before the start of the next Premier League season.
Sport go on to claim that Manchester United have promised De Ligt that he’ll be portrayed the “poster boy” at the club as Ole Gunnar Solskjaer looks to rebuild the Old Trafford outfit.
De Ligt earned plenty of plaudits for his performances in a relatively inexperienced Ajax team in the Champions League this season.
The Dutch club earned unlikely victories away at Real Madrid and Juventus to secure their progress to the semi-finals.
However, Ajax lost 3-2 at home to Tottenham Hotspur in the second leg to crash out of the competition on away goals.
Manchester United failed to finish in the top four and qualify for the Champions League last season, which could act as a deterrent for De Ligt.
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