Dembele reportedly dropped from PSG squad for Arsenal trip
Dembele's absence is not injury-related but "a decision of the coach" Luis Enrique, the source told AFP.
It appears to be a disciplinary measure following a heated exchange between Luis Enrique and Dembele after Friday's 3-1 win over Rennes in Ligue 1, according to sports daily L'Equipe.
Without the in-form Dembele, who has four goals and three assists in six league games this season, PSG will rely more heavily on Bradley Barcola.
Barcola is the leading scorer in the French top flight this term with six goals, two of which came in the victory over Rennes.
Marco Asensio is in a race against time to be fit after picking up an injury in PSG's Champions League opener against Girona two weeks ago.