The Algerian winger is enjoying another successful season with the Citizens, contributing 22 goals from 36 appearances across all competitions.
However, the 31-year-old Riyad has just 15 months remaining on his present deal, inevitably leading to suitors for his signature.
According to a report from a French source Footmercato, the Blues, Real Madrid and Blaugrana are all watching the situation as they anticipate the former Leicester City man potentially being made available later this year.
At this moment, that remains unlikely, but the Etihad Stadium outfit are not expected to risk losing a star of his status for free at the end of next term.
He has lifted two Premier League trophies, one FA Cup and three EFL Cups since switching to Pep Guardiola’s side in 2018.
Elsewhere, Chelsea skipper Cesar Azpilicueta is allegedly struggling to make up his mind over his long-term future.
According to The Express, the Spaniard is torn between his loyalty to the Blues and the chance to return to his homeland to represent Barcelona.
He has again been a key player for his side during the 2021-22 term, scoring twice and notching three assists in 35 outings in all competitions.