Ahmad al-Raysuni said in a statement that the group has a history of serving Islam and accusing it of terrorism and crimes without any evidence is not acceptable, Anadolu Agency reported.
The statement, also signed by IUMS Secretary General Al-Qaradaghi, added that the Muslim Brotherhood plays a major political and ideological role in many countries.
It came after the Council of Senior Scholars of Saudi Arabia and the Fatwa Council of the United Arab Emirates described the Muslim Brotherhood as a terrorist group that does not represent Islam and its actions run counter to the teachings of the religion.
The Muslim Brotherhood was founded in 1928 in Egypt and initially used violence in an effort to push for society to be governed by Islamic law. The organization renounced violence in 1970s and largely turned toward democratic efforts.