The centre-back is still expected to leave Spurs this summer after rejecting a contract extension worth around £120,000 a week, with Manchester United interested.
Standard Sport understands talks between the two clubs have reached an impasse with Daniel Levy demanding in excess of £55 million for the 29-year-old.
Alderweireld did not play in the Premier League last season between October and April, first due to injury but then ongoing uncertainty over his future despite insisting he was match fit.
When asked by Belgian publication Het Nieuwsblad about what await this summer, Alderweireld said: "I really do not know anything yet. In my head I just go to Tottenham. We will see."
He added: "I was very focused on [the World Cup]. I wanted to prove something again. Show that the period before the tournament in which I did not play – for whatever reason – was unjustified.
"I wanted to show that I am still the same Toby as in November."