Iran's relations with its Gulf neighbors such as Saudi Arabia and the United Arab Emirates (UAE), along with the United States, are tense after a terrorist attack on a military parade in the Iranian city of Ahvaz on Sunday left at least 25 people dead.  Both the "Islamic State" (IS) and Arab separatists groups in Iran have claimed responsibility for the attack. 

The Iranian government pointed fingers at its regional rivals, the Saudis and the UAE, as well as at the US for backing the attackers. "Based on reports, this cowardly act was done by the people who are rescued by the Americans when they are in trouble in Syria and Iraq, and are paid by Saudi Arabia and the United Arab Emirates," Iran's supreme leader, Ayatollah Ali Khamenei, said Monday on his official website. The same day the deputy head of the Iranian Revolutionary Guard warned the US and Israel, a close American ally and Iran's perpetual enemy, on Monday that they should expect a "devastating response" from the Islamic Republic. 

So far Saudis have responded to Iran's announcement with silence while the UAE's foreign minister, Anwar Gargash, tweeted "formal incitement against the UAE from within Iran is unfortunate, and has escalated after the Ahvaz attack." "Tehran's allegations are baseless," he added. The US responded by saying that Iran "should look in the mirror." 

Terrorist attack on a national holiday

Holly Dagres, an Iran expert and nonresident fellow at the Atlantic Council in Washington, DC, told DW that the terrorist attack on the military parade was a "big deal" for the Iranians, as the celebration marked the start of the bloody Iran-Iraq war that lasted from 1980 to 1988.

"This was essentially Iran's Memorial Day, with parades happening all around the country," she said. "In Ahvaz, the parade wasn't just attended by members of the army and the Iranian Revolutonary Guard, but also by veterans of the war, as well as families with young children."  

Dagres said that Iran's threats made against its Gulf neighbors and the US seem to be a case of saber rattling. "Tehran isn't in a position to make good on its threats in lieu of the pressure resulting from the United States reimposing sanctions," she said, adding that the goal is to show that "the Iranian government is in a position of strength after the Ahvaz terrorist attacks."  

Iran says Saudi Arabia, UAE support Arab separatists

In Iran, there is a growing consensus that Arab separatist groups were likely behind the attack. Iranian Brigadier General Abolfazl Shekarchi told the state news agency IRNA Monday that the "the terrorists have undergone training in two countries in the Persian Gulf" and that they were not from IS. 

Arab separatists in Iran allege that Iran's ethnic Persian majority discriminates against them. They are seeking independence for Khuzestan, a province bordering Iraq where Ahvaz is also located. The Iranian Foreign Ministry also believes that the UAE and its Gulf neighbors are harboring members of these movements.

Although there is no concrete evidence that Arab separatist groups in Iran receive support from Saudi Arabia and Gulf nations such as the UAE, Dagres said that it could be possible. "Separatist movements, whether they be in Khuzetan or Sistan and Balochistan provinces, would gain a lot from the backing of a state such as Saudi Arabia," she noted. "State backing could provide them not just with funding and moral support, but international legitimacy."

Military conflict not on the horizon, experts say  

Saudi Arabia and Iran maintain a fraught relationship; The two countries  cut ties in January 2016. In the past, Saudi Crown Prince Mohammed bin Salman has made threats towards Iran, warning of consequences should the Islamic Republic take military action or endanger the kingdom's national security. In a 2017 interview the Saudi prince went further, saying, "We are not waiting until there becomes a battle in Saudi Arabia, so we will work so that it becomes a battle for them in Iran and not in Saudi Arabia."   

Although experts say the attack in Ahvaz will ratchet up tension between the two nations, they view a consequent military conflict as unlikely.  "I don't think that this will lead to a direct military conflict between Iran and Saudi Arabia," Jens Heibach, a Saudi Arabia expert and research fellow at the GIGA Institute of Middle East Studies in Hamburg, told DW.  "Saudi Arabia is already engaged in a costly military conflict, such as the war in Yemen. Plus the Saudi army would not be in a position to conventionally challenge Iran's military."

Dagres also agreed with the notion that escalation between Tehran and Riyadh was unlikely, also pointing out that "any direct conflict between Saudi Arabia and Iran, two regional powers, would draw in the world powers like the United States."

Read more: Saudi Arabia vs. Iran: From 'twin pillars' to proxy wars   

Iran could respond by "heating up" proxy wars in the region, Dagres said. It could use proxy groups such as Hezbollah in Lebanon or Syria to direct more attacks towards Israel, a close American ally. Iran could also provide more military support to the Houthis in Yemen, who have in the past shot rockets at Saudi Arabia. "Iran would most likely not directly retaliate against Saudi Arabia but rather depend on its [Iran's] proxies in the region to send a message," she said. 

US seeking to isolate Iran

Any such retaliatory action by Iran would draw the ire of the United States, which under the Trump administration is pushing to isolate Iran from the international community and to lessen Iranian influence in the region. "The tension is likely to escalate," Emad Abdul Hadi, a political analyst in Washington, DC, told DW. "The United States will not accept less than Iran's withdrawal from Arab countries in the region, such as Syria and Iraq."

Diplomatic animosity between the US and Iran will be on display this week as President Trump attempts to convince the United Nations that Iran is a sponsor of terrorism in the region and justify America's decision to pull out of the Iranian nuclear deal.     

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