A Saudi-led Arab bloc arrayed against Qatar -- including Saudi Arabia, Egypt, the United Arab Emirates and Bahrain -- announced late Wednesday that it had added two entities and 11 individuals to its terrorist list.
The additions include two Doha-based NGOs: The International Islamic Council and the International Union of Muslim Scholars (IUMS) led by prominent Egyptian scholar Sheikh Yusuf al-Qaradawi.
The four countries said in a joint statement that the entities added to the list constituted "terrorist organizations working to promote terrorism through the exploitation of Islamic discourse, which they use as cover to carry out various terrorist activities."
"The 11 individuals [added to the list] have carried out various terrorist operations for which they received direct Qatari support," the statement -- carried by Saudi, Egyptian and Bahraini news agencies -- read.
The Saudi-led quartet also added 11 individuals to their lists, including the acting Brotherhood leader Mahmoud Ezzat Ibrahim.
The Muslim Brotherhood movement led the Arab Spring protests in 2011 that toppled some autocrats in the Middle East and North Africa. The Gulf States' rulers see the group, whose political ideology challenges the principle of dynastic rule, as a security threat.
The IUMS has yet to comment on the development.
The move deepened the rift between the four countries and Qatar, the world's top gas exporter and host to the biggest U.S. military base in the Middle East. The countries cut ties with Qatar in June, accusing it of financing militants in Syria and allying with Iran, their regional foe.
In June, Saudi Arabia, the UAE, Egypt and Bahrain abruptly cut diplomatic and commercial ties with Qatar, accusing it of supporting terrorist groups in the region.
Qatar, for its part, has denied the accusations, describing the attempts to isolate it as a breach of international law.
The move deepened the rift between the four countries and Qatar, the world's top gas exporter and host to the biggest U.S. military base in the Middle East. The countries cut ties with Qatar in June, accusing it of financing militants in Syria and allying with Iran, their regional foe.
Mediation efforts of the Qatar crisis led by Kuwait and shuttle diplomacy by Western officials, including U.S. Secretary of State Rex Tillerson, have failed to end what has become the worst rift between Gulf Arab states in years.