The 23-year-old has made 138 appearances for Spurs since joining from Metz in 2021, contributing 11 goals and 10 assists.
His future at the club has become increasingly uncertain given Tottenham's relegation battle and the likelihood of significant summer changes whoever manages them next season.
Turkish outlet Fotomaç reports that talks are underway, with Fenerbahce viewing Sarr as a priority target.
The Istanbul club are managed by former Belgium coach Domenico Tedesco and are prepared to pay in the region of €35 million for the midfielder, which would represent their record signing. Galatasaray have also been credited with interest, adding a competitive dimension to the pursuit.
Fred joined Fenerbahce from Manchester United in 2023 for £8.6 million after five seasons at Old Trafford, but his future at the club is now uncertain as they assess their midfield options for next season.
Sarr is contracted at Tottenham until 2030, giving the north London club a strong negotiating position if they choose to sell.
Spurs declined to exercise an option to sign Yves Bissouma on a permanent basis, indicating a wider midfield overhaul is likely regardless of whether the club avoids relegation.