The Evening Standard is reporting that the Red Devils are prepared to pay up to £40m to secure the signature of the Belgian defender as Jose Mourinho looks to add some experience to his rearguard.
The same story says that Tottenham are getting ready to sell Alderweireld after failing to agree a new deal with the 29-year-old – and they plan to spend the funds on Ajax starlet Matthijs de Ligt.
It is also claimed that the likes of Chelsea FC, Paris-Saint Germain and FC Barcelona are all interested in the defender – but Manchester United are prepared to significantly increase his wages at Old Trafford.
It is also suggested that Manchester United are willing to give Alderweireld a long-term deal to keep him at the club until his mid 30s.
Manchester United are likely to be on the lookout for a number of top signings this summer as Mourinho looks to build a squad capable of winning the Premier League title next season.
The Red Devils finished as runners up to Manchester City last term in the top flight.
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