Antonio Conte's side are on course to secure their fifth title of the modern era but Spurs hit back this afternoon to cut the Blues' lead to 10 points with a 2-1 victory over Southampton.
Christian Eriksen's long-range effort and Dele Alli's penalty put Mauricio Pochettino's side in control at the break, despite Harry Kane's absence.
But the north Londoners were forced to endure a nervy second half as James Ward-Prowse beat Hugo Lloris with a near post finish to set up a tense finale.
But Pochettino's men held their nerve and Vertonghen is adamant he and his teammates are not ready to concede that the title race is over until it is no long mathematically possible.
"Chelsea are favourites for the title but we won't give up until they lift the trophy. We are doing well and have to aim for the highest place possible and keep winning our games," he told Sky Sorts.
"We had to work very hard. Southampton are a great team with great players. We were lucky to be 2-0 up at half time and then had to get the third one but didn’t," the Belgian added.
Chelsea are in a commanding position at the top of the table, despite Tottenham's victory, having edged past Stoke City on Saturday.
The Blues need 21 points from their remaining 10 top-flight fixtures to be crowned champions and only a dramatic collapse - plus a flawless finish to the campaign by Spurs - would be likely to see Conte's side pipped at the post.