Allies of Saudi Arabia followed the kingdom's lead Monday and scaled back diplomatic ties to Iran after the ransacking of Saudi's embassy in Tehran -- violence sparked by the Saudi execution of a prominent Shiite cleric.
Some analysts say the Saudi government executed Sheik Nimr al-Nimr - along with 46 other people on terrorism-related charges - to show its crackdowns have not focused exclusively on Sunni clerics critical of the kingdom.
Bahrain, Sudan, and the United Arab Emirates have all downgraded ties with Iran. White House spokesman Josh Earnest says the U.S. is concerned about the situation and wants Saudi Arabia and Iran to show restraint. He's urging them not to inflame tensions or further sectarian conflict. Earnest says it's in the interests of Iran and Saudi Arabia to continue working toward a political solution for Syria. Both countries have been participating in the talks in Vienna.
Who was Al-Nimr and why was he executed? What’s the risk and benefit of Saudi executing him? What does this illustrate about the new king?
How might the dispute continue to play out regionally? What are the economic and security consequences for both countries and the region as a whole?
With files from the Associated Press.