Saudi Arabia has listed the Muslim Brotherhood and a number of other groups as terrorist organizations. The Brotherhood has been the target of many Gulf nations since Egypt's Mohammed Morsi was ousted last July.
Friday's announcement appeared to enforce the findings of a royal decree last month, in which Riyadh promised to punish those who fight in conflicts outside the kingdom, or join or support extremist groups.
A list published by the official Saudi Press Agency lists as terrorist organizations the Muslim Brotherhood, the Al-Nusra front - al Qaeda's official Syrian affiliate - as well as the branches of al Qaeda in Yemen and Iraq, Saudi Hezbollah and Yemen's Shiite Hawthis.
The interior ministry said it would prosecute anyone backing these groups "financially or morally," or who express sympathies for or promote them. Saudi Arabia also forbade citizens from fighting in conflict zones, giving Saudis fighting abroad a 15-day ultimatum to return home or face imprisonment.
The decrees on Friday represent an escalation against the Brotherhood of ousted Islamist Egyptian president Mohammed Morsi, with Riyahd fearful the group has tried to build support inside the kingdom since the Arab Spring revolutions. The Brotherhood's Sunni Islamist doctrines challenge the Saudi principle of dynastic rule.
There is also concern in Riyadh over the potential domestic security risks of Saudi extremists fighting in Syria. The Saudi interior ministry estimates around 1,200 Saudis have gone to Syria to fight, heightening worries that fighters could become radicalized and then return to Saudi Arabia and turn their weapons on the monarchy.
Riyadh, however, strongly supports some rebel opposition groups with weapons and aid, in their battle to overthrow Syrian President Bashar al-Assad.
Pressure on Qatar
Saudi Arabia's move against the Muslim Brotherhood is likely to heap pressure on Qatar, whose backing of the group and others Islamist organizations in the region has caused a row with fellow Gulf monarchies. It comes two days after Saudi Arabia, Bahrain and the United Arab Emirates recalled their ambassadors from Qatar.
The three said Doha had not stuck by an accord not to interfere in each others' internal affairs.
Egypt formally declared the Muslim Brotherhood a terrorist organization in December. The group has been the target of a deadly crackdown since Morsi's army-led ouster.
jr/ph (AFP, AP, Reuters)