Is the Bank of Egypt (Tal'at Harb) investment certificate with a 20% interest rate permissible or forbidden?

Investment certificates with a guaranteed fixed return are usury (riba) and it is not permissible to invest in them, because they cause the loss of blessing, and because Allah has cursed those who deal in usury and those who cooperate with them. The Prophet, peace and blessings be upon him, said: "Allah has cursed the one who consumes usury, the one who gives it, the one who writes it down, and the two who witness it." He added: "They are all alike [in sin]." Therefore, it is not permissible to participate in them.