​Manchester United are unwilling to match ​Tottenham's demands for Toby Alderweireld and will walk away from the deal unless a compromise can be reached imminently.

The Belgian defender is keen on a move to Old Trafford and ​is among United's key targets, but they will look elsewhere if Spurs do not lower their asking price.

​The Independent understands that United's bid for Alderweireld, rumoured to be in the region of £55m, falls short of Tottenham's valuation for the 29-year-old centre back.

The £75m fee that ​Liverpool paid ​Southampton for Virgil van Dijk in January has changed the notion of what a top-class defender is worth, and Tottenham are understood to want a similar fee if they are to part with Alderweireld.

United are unwilling to spend that sort of money on a defender and have told Tottenham that they will walk away from the deal unless the demands are lowered.

However, this may just be a smart piece of negotiation from United, and they must wait to see if Daniel Levy will call their bluff.

With Alderweireld refusing to sign a new contract and his current deal set for expiry next summer, Spurs will have to sell the Belgian either this summer or in January if they want to get a satisfactory sum.

The club can activate a one-year extension on Alderweireld's contract when it runs out next year, but a clause in the contract means that they will be obliged to sell for £25m from July 2019 onwards.

Tottenham Hotspur v Real Madrid - UEFA Champions League

A hamstring injury kept Alderweireld sidelined for most of the 2017/18 season as he made just 14 ​Premier League appearances - but he should feature for Belgium at the World Cup this summer.