The Club World Cup regulations do not allow more than one club from the host country to participate in the annual tournament. Casablanca-based side Wydad will already take part as the reigning African champions.
Wydad won the Champions League after beating Ahly 2-0 in the final last May.
"The club has received a letter from FIFA confirming its participation in the Club World Cup," Ahly said in a brief statement.
The Red Devils will make a third straight appearance in the seven-team tournament. They finished third in their previous two participations after winning back-to-back Champions League titles.
The Club World Cup will take place in Morocco from 1-11 February.
FIFA said earlier on Friday that an expanded 32-team edition of the tournament will be inaugurated in 2025.
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