News of President Abdel-Fattah el-Sissi's ratification of the maritime border demarcation agreement came in a Cabinet statement issued today.
The ratification followed the June 14 approval of the agreement by parliament, despite court rulings to annul the transfer.
The government says the two islands have always been Saudi but were placed under Egypt's protection in the 1950's amid Arab-Israeli tension. Critics say the islands were transferred in exchange for billions of dollars of Saudi aid.
Authorities earlier this month arrested an estimated 120 people who voiced opposition to the agreement or demonstrated against it in street protests. Most have since been released.