Egypt's Al-Azhar has issued a fatwa banning membership to the Muslim Brotherhood.
"It has become clear to the public what these groups have done in distorting some texts, cutting them out of their context, and using them to achieve personal goals or interests and corrupting the land," the university's fatwa centre said.
"Membership in these extremist groups is considered forbidden by Shariah."
It comes on the heels of similar moves made by Saudi Arabia and the UAE, whose fatwa councils have designated the group as a "terror organisation".
In November, the UAE Fatwa Council agreed with a statement issued by the Council of Senior Scholars of Saudi Arabia considering the Brotherhood a terror organisation, "due to its support for violent extremist groups, disputes with leaderships and disobedience."
The Saudi senior scholars said: "Sharia promotes unity and warns against division and rogue groups," calling on "all Muslims to denounce divisions and avoid supporting, sympathising with, and joining organisations that aim to instigate divisions, trigger conflicts and shed blood."
Around this time Egypt's Grand Mufti, Shawki Allam, said that it is "religiously forbidden" to belong to the Muslim Brotherhood because they incite violence.
Allam praised the Saudi scholars' decision.
Shortly after the 2013 coup in Egypt, the Muslim Brotherhood was outlawed and top leaders and members rounded up in a widespread crackdown. The organisation was listed as a terror group.
In jail, its members are tortured, denied medical care and many are sentenced to death.
Members of the opposition are accused of being part of the group, including Christians and outspoken Brotherhood critics.