File photo of Zamalek winger Mostafa Fathi (Ahram)
Fathi, whose deal with Zamalek was due to expire at the end of the season, will pen a three-year deal with Al-Taawoun, Mansour said in a video message carried by the club's social media accounts.
The 27-year-old re-joins the club where he spent a loan spell in the 2017-18 season, scoring five goals in 11 appearances.
He excelled while on loan at Alexandria-based club Smouha last season, prompting Zamalek to rely on him as a regular starter this term.
Fathi made a superb start to the season, scoring four goals in the opening eight games of the season and providing an assist. His goal included a brilliant screamer against Ahly in Zamalek's 5-3 Cairo derby defeat in November.
He also earned an Egypt call-up for the FIFA Arab Cup last month but was overlooked for the ongoing African Cup of Nations in Cameroon.
Fathi is one of a handful of players that the cash-strapped Zamalek risk to lose at the end of the season when their deals run out. Those players include key Moroccan duo Achraf Bencharki and Mohamed Ounajem as well as defensive midfielder Tarek Hamed.
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