Saudi-Iran row: Kerry calls leaders to urge calm
US Secretary of State John Kerry has repeatedly called leaders in Saudi Arabia and Iran to try to defuse their diplomatic row, US officials say.
State department spokesman John Kirby said the phone conversations involved foreign ministers of both countries and the Saudi deputy crown prince.
Saudi Arabia cut diplomatic ties with Iran on Sunday after protesters ransacked the Saudi embassy in Tehran.
Protests erupted after Saudi Arabia executed a senior Shia Muslim cleric.
Sunni Muslim Saudi Arabia and Shia Iran are major rivals in the Middle East and back opposing sides in the conflicts in Syria and Yemen.
In his calls, Mr Kerry stressed the importance of pushing forward on a peace deal for Syria, Mr Kirby told a news conference.
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"One of the key things on his mind is de-escalate the tensions, restore some sense of calm, encourage dialogue and engagement between these countries, but also to make the point there are other pressing issues in the region," Mr Kirby said.
"Not letting the Vienna process [on Syrian peace talks] stall or fall backward is clearly top on his list," he said.
On Tuesday, Kuwait said it was recalling its ambassador from Tehran, describing the attack on the Saudi embassy there as a "flagrant breach of international norms".
Saudi allies Bahrain and Sudan broke off diplomatic relations with Iran on Monday and the United Arab Emirates (UAE) has also downgraded its diplomatic team in Tehran.
On Monday, the UN Security Council issued a strongly worded statement condemning the attack on the Saudi embassy - making no mention of the execution of Shia Muslim cleric Sheikh Nimr al-Nimr and 46 others on terrorism charges.
Turkey has also called for calm, warning that the feud could worsen regional tensions.
Iran has responded angrily to the diplomatic moves, insisting it had no hand in the violent protests that followed the execution.
President Hassan Rouhani said on Tuesday that Saudi Arabia could not "hide its crime of beheading a religious leader by severing political relations with Iran".
- The split arises from a dispute soon after the death of the Prophet Muhammad in 632 over who should lead the Muslim community
- Sunnis are estimated to make up between 85% and 90% of Muslims
- Although the two branches have co-existed for centuries and share many fundamental beliefs and practices, differences lie in the fields of doctrine, ritual, law, theology and religious organisation