Tottenham are nine points behind surprise leaders Leicester with Arsenal and Manchester City ahead of them in the Premier League table.
"We can say we want to get nine points from the next three games but it's difficult to do that," he said, adding that the team is not looking beyond the Boxing Day clash with Norwich City for now.
The Belgium international pointed to Norwich's win over Manchester United last weekend as an example of the competitiveness of England's top-flight.
Rival teams do not look forward to playing at White Hart Lane, Vertonghen added. Spurs have lost just once at home in the last eight games in all competitions.
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Mauricio Pochettino's men enter the festive period with the joint best defensive record in the league along with fierce rivals Arsenal and Manchester United. After the Norwich game, Spurs will take on Watford and Everton.
(Reporting by Chris Peters in Bengaluru; editing by Sudipto Ganguly)
