Other Arab governments also decided to take action. The United Arab Emirates announced it would downgrade ties to Tehran to the level of the charge d'affaires. Mauritania issued a statement condemning the "acts of vandalism" in Tehran. Egypt denounced the attacks on Saudi diplomatic missions in Iran as "unacceptable".
As the crisis between the two regional powers, Saudi Arabia and Iran, worsens, the Security Council also issued a statement last night urging all sides to "take steps to reduce tensions in the region".
The council made no mention of the event that set off the crisis, i.e. Saudi Arabia's execution on Saturday of Sheikh Nimr al-Nimr, a cleric and activist who defended Shia rights and was critical of Saudi Arabia’s ruling family. Although he fought non-violently, he was executed as a “terrorist”. His death sparked widespread protests among Shias.
Iranian President Hassan Rouhani condemned the attacks and Iran’s mission to the United Nations vowed in a letter to the Security Council to "take necessary measures to prevent the occurrence of similar incidents in the future".
The United Nations is concerned that the heightened Saudi-Iran regional rivalry might derail the already shaky peace efforts in Syria and Yemen, where the two countries have sided with opposite belligerents.
Western powers have sought to calm the tensions. Moscow said it was ready to act as a mediator.
UN envoy for Syria, Staffan de Mistura, was en route to Riyadh and later Tehran to defuse tensions.
Abdullah al-Mouallimi, the Saudi Ambassador to the UN, said on Monday that the row with Tehran "should have no effect" on attempts to end the region’s wars.
The crisis between Tehran and Riyadh has found its way into the world of sport. Saudi football clubs in the Asian Champions League have called for the matches against their Iranian counterparts to be played on neutral grounds.