So far so good: Arab States Show Cautious Optimism on Nuclear Deal - Saudis Voice Fears That Iran Will Press Influence in Region

From The Wall Street Journal:

Saudi Arabia maintained a pointed silence Sunday on the new nuclear pact between world powers and Saudi Arabia's top rival, Iran, while other Gulf and Arab states gave a cautious welcome to a deal hoped to ease tensions in a region bloodied by proxy battles between Shiite Iran and Sunni Arab states.

Saudi political commentators voiced persistent fears that Iran would now see itself as freed to advance on other, non-nuclear fronts against its Middle East rivals.
 
By early Monday in the Middle East, most of the region's Muslim powers—Turkey, Egypt, and at least four of the six wealthy Arab Gulf countries—had issued statements expressing support for the deal. The United Arab Emirates., a commerce-minded nation that traditionally has thrived on doing business with both Iran and Arab states, welcomed the deal as one it hoped would protect the region "from the tension and danger of nuclear proliferation," the emirates' council of ministers said.
 
However, Saudi Arabia's silence after the deal, as other Arab and Muslim states expressed guarded approval at the diplomatic effort in Geneva, emphasized abiding Saudi distrust of Iran, and suggested distrust of the new deal as well.
 
Arab Gulf states hope a solid deal barring Iran from developing a nuclear-weapons program "will take away competition…for an arms race" in the region, said Jamal Khashoggi, a veteran political commentator and journalist in Saudi Arabia.