England international Dier has less than a year left on his current contract and has an eye on leaving on a free transfer next summer.
However, the London-based club are not keen on that prospect and have offered Dier to several sides, including German champions Bayern Munich.
Tottenham are already thinking about what might happen if Dier goes and, according to Belgian journalist Sacha Tavolieri, they admire the profile of Belgium international Faes.
Faes is on the books at Leicester and could depart before the window closes.
The six-foot-two-inch defender joined the Foxes only last summer but could not help them avoid relegation.
He is not keen on staying put in the English second tier and has interest from Turkish side Galatasaray as well.
Faes though could jump at the prospect of a move back to the Premier League with Tottenham if it is offered to him.
