When asked whether Spurs intend to trigger the clause, Pochettino told a news conference: "Yes, for sure, it's obvious. The same situation as Jan (Vertonghen)."
Earlier this month, Spurs extended centre back Vertonghen's contract until 2020.
Alderweireld, who arrived at Spurs in July 2015 from Atletico Madrid, has been a key player for the north London outfit this season, making 24 appearances in all competitions.
Having won their last five Premier League games, Spurs have crept up to second spot and are six points behind leaders Liverpool.
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But Pochettino said it is still premature to talk of Tottenham as title contenders.
"We are there because we have the belief, because we are working hard and of course we have the quality," he said.
"It is hard to be in the position that we are in. Still we are a question mark. We will see if we are capable during the whole season to be consistent like in the first half of the season. Then we can talk that we can fight for big things."
Spurs said full back Serge Aurier has returned to training after recovering from a groin problem, while midfielder Dele Alli will be assessed ahead of Saturday's league clash against Wolverhampton Wanderers.
Alli missed the 5-0 victory over Bournemouth on Boxing Day, having been substituted during last weekend's 6-2 triumph at Everton over a hamstring concern.
(Reporting by Hardik Vyas in Bengaluru)
