Saudi Arabia gave an apparent warning to regional rival Iran on Wednesday not to intervene in the conflict in Iraq which it said could escalate to full civil war with implications beyond Iraqi frontiers.
The United Arab Emirates (UAE), a fellow Sunni Muslim Gulf dynasty, announced it was recalling its envoy to Baghdad for consultations, and criticised what it called the sectarian policies of Iraq's government, an ally of Shi'ite power Iran.
Their statements coincided with an Iranian warning that Tehran would not hesitate to defend Shi'ite Muslim holy sites in Iraq against "killers and terrorists", following advances by Sunni militants there.
The toughening rhetoric about Iraq from Gulf powers on both sides of the region's Sunni-Shi'ite sectarian divide suggested that Tehran and Riyadh have put on hold recent plans to discuss curbing their long rivalry.
The sectarian edge to the Saudi-Iran struggle has sharpened in the last few years. The two see themselves as representatives of opposing visions of Islam: the Saudis as guardians of Mecca and conservative Sunni hierarchy, and Shi'ite Iran as the vanguard of an Islamic revolution in support of the downtrodden.
Speaking at a gathering of Arab and Muslim leaders in Jeddah, Saudi Foreign Minister Prince Saud Al Faisal said Iraq was facing a civil war with grave consequences for the wider region.
Prince Saud urged nations racked by violence to meet the "legitimate demands of the people and to achieve national reconciliation (without) foreign interference or outside agendas".
"This grave situation that is storming Iraq carries with it the signs of civil war whose implications for the region we cannot fathom," he said.
He did not elaborate but the remarks appeared aimed at Shi'ite Iran, which is also an ally of the government of Syrian President Bashar Al Assad.
The prince said the three-year-old civil war in Syria, where a largely Sunni Muslim uprising has failed to unseat Assad, had "helped to deepen the internal disturbance in Iraq".
Announcing the recall of its envoy, the UAE said it was worried that the Iraqi government's "sectarian" policies could heighten political tensions and worsen security there.
In a statement on the official WAM news agency, the foreign ministry added that the UAE opposed any interference in Iraq's affairs and sought the creation of a national unity government.
"The ministry expressed its deep concern at the policy of exclusion, sectarianism and marginalisation of basic components of the Iraqi people," the statement said.
The UAE reaffirmed its condemnation of the "terrorism" of the Sunni Islamic State of Iraq and the Levant (ISIL), which it said had led to the killing of many innocent Iraqis.
Iraq's Prime Minister Nuri Al Maliki, an ally of Iran, has appealed for national unity with Sunni critics of his Shi'ite-led government after a stunning offensive through the north of the country by ISIL over the past week.
Maliki has accused Saudi Arabia of backing ISIL, who want to carve out a Sunni caliphate in the heart of the Middle East.
On Monday, Saudi Arabia blamed the Iraqi crisis on Maliki, citing what it called years of "sectarian and exclusionary policies" by his government against Iraq's Sunni minority.
Maliki and several Iranian officials have for months alleged that several Gulf Arab governments support ISIL.
And on Saturday, Iran's President Hassan Rouhani said that "terrorist groups" were getting backing and weaponry from countries in the region and powerful Western states. He named no countries, but was alluding in part to Sunni Gulf Arabs.
Western diplomats say it is private Gulf Arab donors who follow an ultraconservative brand of Sunni Islam who appear the more likely source of ISIL's funding from the Gulf.
While the Saudi government has yet to specifically condemn ISIL by name, the group is no friend of Riyadh's, having battled the kingdom's allies in infighting among Sunni rebels in Syria.
Not only do Tehran and Riyadh share the fear that Iraq may disintegrate into a sectarian bloodbath, in the short term ISIL's advance is likely to raise suspicions between them.
While Tehran sees Gulf Arab hands behind ISIL, Riyadh fears not only that Iran will intervene in Iraq but that it will do so in coordination with Iran's traditional adversary Washington, which is equally keen to roll back ISIL's territorial gains.
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