According to Foot Mercato, Monaco have renewed their interest in the Mauritania international after previously trying to sign him during the winter transfer window.
The Ligue 1 club are reportedly still keen on the Paris Saint-Germain academy graduate, who won the French title in 2022.
Rangers are understood to be open to Gassama’s departure but will demand at least €10m for the forward, whose contract runs until 2029.
Gassama joined Rangers from Sheffield Wednesday last summer and enjoyed an impressive debut campaign in Glasgow.
He made 56 appearances across all competitions, starting 40 games, while contributing nine goals and six assists last season.
