Tottenham Transfer News: Toby Alderweireld Fears Reported Amid Contract Rumours

Tottenham Hotspur are reportedly growing "increasingly concerned" they will have to sell centre-back Toby Alderweireld this summer as talks between the two parties continue.

MailOnline's Sami Mokbel reported a clause in the Belgium international's contract allows Spurs to extend his contract beyond its current 2019 expiration date, but that would then activate a £25 million release clause in his deal.

The decision to extend Alderweireld's current terms could leave Tottenham open to losing their star centre-back for significantly less than his market value.

The 28-year-old is currently sidelined through injury, although the Press Association's Tom Allnutt saw a positive impact of him not being able to push for a move during the winter transfer market:

Spurs manager Mauricio Pochettino recently sought to soothe fans' fears when quizzed on Alderweireld's contract situation, per Alasdair Gold of football.london:

“This is a message for our fans and for everyone, he still has two-and-half-years of his contract. Messi had six months left on his contract. Messi!

"Nothing happens. If something happens, the club is going to communicate. But I don't understand all these things when the players are all under contract."

Alderweireld earns £50,000 per week in north London but is said to be seeking a contract worth more than double that figure and wants to see the club break their £110,000-per-week limit, per Mokbel's report.

He joined Tottenham from Atletico Madrid in the summer of 2015 and has grown to become arguably the most valuable piece of Pochettino's defence.

The South American reacted to the news of Alderweireld's absence in December and outlined his importance to the team, per Gold:

Tottenham now face a dilemma in convincing Alderweireld to pen new terms at the club while convincing him to agree a salary he won't feel can be easily matched elsewhere.

The longer it takes Tottenham to negotiate a new contract with their star, the closer he moves to the end of his deal and is at risk of becoming a potential free departure in 2019.