The Black Cats made their first January acquisition this week after bringing in Alfred N’Diaye in a £3.8million move from Turkish outfit Bursaspor.
But Sunderland are said to be readying a £3.5m bid for Sissoko, with Toulouse eager to cash in on the 25-year-old, rather than lose him for nothing in the summer.
There is no shortage of interest in the 22-year-old though, with Marseille, Monaco and Spurs also tracking him.
