Tel joined Spurs on loan in January to the end of this season, with a permanent option worth €55 million (£47.7 million).
Sky Deutschland's Florian Plettenberg is reporting: "Tottenham Hotspur are happy with Mathys Tel and are considering a permanent move for, but no final decision has been made yet.
"Understand Spurs definitely want to renegotiate with FC Bayern and are not willing to activate the €50–55 million clause as a buy option."
Tel has scored two goals in ten matches for Spurs so far this season.