"We have sealed Mahmoud's deal. He signed a three-year contract with Ittihad," chairman Mohamed Moselhi told FilGoal.com.
The ex-Zamalek defender will receive EGP 500,000 in his first season, with a rise of 50,000 every year.
In the meantime, Ittihad board member Hisham Al-Torki added that Mahmoud will be followed by a number of new signings during the off-season.
"We will soon be holding talks with Zamalek full-back Osama Hassan as well as Police striker Ahmed Sonbol," Al-Torki confirmed.
On the other side, the Alexandria club will be offloading no less than nine first team players.
Defender Mohamed Abou-Khangar decided to leave the club upon signing Mahmoud.
Forward Sameh Youssef will be joining newly-promoted Military Production.
Haytham Al-Fazani, Mohamed Abdul-Sattar, Adel Fathi, Essam Bakr, Awuley Quaye, Ibrahim Abdul-Razak and Nasigba John-Jumbo will all be released upon coach Taha Basri's request.