Alderweireld’s future has been a source of debate in the summer transfer window so far given the 30-year-old has less than 12 months left to run on his current deal.
The Belgium international is in a unique position where the versatile defender is available for a mere £25m due to a clause in his contract that is set to expire on Friday.
Arsenal have been heavily linked with a swoop to sign 18-year-old Saint Etienne defender William Saliba this summer despite their urgent need to make immediate improvements at the back.
Manchester United are in a similar position considering that the Red Devils conceded more goals than Manchester City and Liverpool FC combined last season.
The Red Devils have already made a £70m bid for Leicester City defender Harry Maguire this summer but the Foxes want a world-record £90m to sell the Englishman.
Former Manchester City full-back Mills has now expressed his surprise that neither Arsenal nor Manchester United have tried to sign Alderweireld in the summer transfer window.
“Let’s say he plays another three seasons, that’s around £8m-a-year,” Mills told Football Insider.
“People are paying loan fees of £8million-a-year, he’s a ready-made player. It’s an absolute bargain.
“How Manchester United are not coming and banging down the door, how Arsenal are not banging down the door and saying we want this player, I have no idea.
“£25m for a ready-made centre-half who is going to get you through the next three seasons and bring on other players around them, it’s a no-brainer for me.
“People will say you’re going to lose money, yeah you are but you’re going to do that if you bring loan players for me.”
Alderweireld helped Tottenham to reach the Champions League final last season before a 2-0 loss to Liverpool FC in the Madrid showpiece.
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