The 29-year-old's contract is running down, and even triggering an extension to take it beyond 2019 would make him available for a meagre £25m next year.
Alderweireld's deal expires in 2019, and while the club can extend it by 12 months, it also contains a £25 million release clause that can be activated next summer as long as there are at least two weeks remaining in the transfer window.
United and Barcelona have been following Alderwiereld's situation for some time, particularly after Manchester City seemingly dropped out of the race by signing Aymeric Laporte.
The 29-year-old centre back is proven as one of the Premier League's most dependable defenders and his contract situation will no doubt mean there are a host of suitors, both from England and overseas, who will be looking to capitalise on an exit which seems more and more likely every day.
Asian shares track U.S. tech slump, focus on Fed meeting
Still, with a Fed rate rise already fully priced in, the dollar barely gained from the prospect of a rate increase. The Dow Jones industrial average fell 335.60 points, or 1.3 percent, to 24,610.91.
PSG are set to chamge their coach this summer due to their early ouster from the Champions League competition, and are ready to back the new man with a healthy transfer budget to improve the squad.
Alderweireld would be a strong addition to any of the sides interested in him, and his loss would be a significant blow to Spurs.
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And that will come in the form of Ultra Street Fighter IV , which, in a way, " completes " the legacy. Sorry Switch fans, you're getting left out of this pre-order bonus, but there's a good reason.
Meanwhile, the French club has identified the center of defence as one of their major weakness, thereby plotting to land the Spurs man.
That is according to the Telegraph, who have claimed that the Spurs defender could be at the center of a three-way tussle as his contract situation in north London rumbles on.
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Coming hot off the heels of the mega-hit, Black Panther , where he played the villain, Erik Killmonger, Michael B. Jordan is now set to produce a World War II drama titled, the Liberators .