Mahmoud was in charge of last week’s game at Cairo Stadium, where the league leaders had a valid goal disallowed and a clear penalty appeal turned down in the first half.

He was due to be investigated by the Egyptian FA’s refereeing committee, but instead he decided to put an end to his career.

“I decided to quit refereeing once and for all,” Mahmoud said in Modern Kora TV.

“I swear to God I had no intention of being unfair toward Zamalek and I apologize to the club and their fans.

“I am not going for any investigation because I committed no crime. Referees do not go under investigation when they are at fault. Such procedures are only for criminals!”

Mahmoud denied allegations claiming he supports Zamalek‘s arch-rivals Ahli as he stressed on his loyalty to Alexandria-based Ittihad.

“I am not an Ahli fan. I am an Alexandrian, that’s why I never officiate matches involving Ittihad,” he added.