When Saudi Arabia's Ministry of Interior announced the execution of the Shia religious leader Nimr al-Nimr on Saturday, many feared that Iraq would inevitably be caught in the dark storm expected to gather over relations between Saudi Arabia and its regional rival Iran.
The question wasn't whether al-Nimr's execution would put Iraq in the midst of the crisis between the two regional heavyweights, but rather to what extent the new conflict will inflame the Iraq's existing sectarian tensions.
Only a day after Riyadh cut its diplomatic ties with Tehran after Iranian protesters stormed its embassy in response to al-Nimr's execution, blasts rocked two Sunni mosques in central Iraq.
A least one man, a muezzin, the person who calls for prayer, was killed in the attacks in two districts of south Baghdad.
Thousands of Iraqi Shia Muslims demonstrated on Monday outside the heavily fortified Green Zone in Baghdad which hosts the Saudi embassy, condemning al-Nimr's execution with some demanding severing relations with Saudi Arabia. There were similar demonstrations in other Iraqi cities.
The protests followed outrage voiced by Iraq's Shia political and religious leaders over the execution of al-Nimr and other Shia activists. Ayatollah Ali al-Sistani, Iraq's most senior Shia authority, blasted the execution as "unjust and an aggression".
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The question now is whether the crisis erupted over al-Nimr's execution will inflame existing ethnic and sectarian tensions in Iraq.
Behind the backlash against the executions, however, lie more serious problems. Iraq is particularly vulnerable to the Iranian-Saudi feud, which threatens to deepen its own lingering sectarian conflict.
Both nations back opposing parties and groups in Iraq and pursue geopolitical interests in the country.
The question now is whether the crisis over al-Nimr's execution will inflame existing ethnic and sectarian tensions in Iraq as its Shia-led government tries to bring the war against the Islamic State of Iraq and the Levant group (ISIL) to a successful conclusion.
The negative effect is due to two mechanisms which are not mutually exclusive: Peripheral, indirectly, through the spillover from Iranian-Saudi rift; and central, due to Shia-Sunni sectarian polarisation inside Iraq.
By and large, the Iranian-Saudi rupture is stoking tension that threatens to derail Iraq's efforts to build a regional and global front in the war against ISIL.
A string of defeats inflicted in recent weeks in Iraq, most recently in Ramadi, have raised hopes that ISIL's demise may be closer than had been thought.
The Iranian-Saudi escalation, which is bound to change the rules of the game in the proxy wars in Iraq, will most probably undermine Baghdad's campaign to defeat ISIL. Saudi-Iran tensions will not only represent yet another hurdle for regional and international action to combat ISIL, but will pit both Iran and Saudi Arabia in a direct confrontation in Iraq.
WATCH: Stern message from Saudi Arabia
Today, Riyadh's new assertiveness - as Nawaf Obaid, a Saudi security adviser, has summed it up in an article in the London-based newspaper Al-Hayat on Tuesday - is all about filling the vacuum in "the leadership of the Arab world" in absence of its "traditional pillars, Egypt, Iraq and Syria".
For Iraq, the rhetoric of this strategy is being translated into Saudi attempts to create a new multipolar regional order which could throw the delicate international coalition against ISIL off balance.
Saudi Arabia's endeavours to create a new Sunni-dominated "Islamic military alliance" devoted to fighting global terrorism, and plans to set up a "strategic cooperation council" with Turkey, are seen by Baghdad as primarily motivated by a regional rivalry with Iran.
On the other hand, the acrimony between Iran and Saudi Arabia could bring more chaos to Iraq. As Monday's bombings of the Sunni mosques have demonstrated the conflict increases fears of renewed Shia-Sunni violence.
The Iran-backed Shia militias, which have been increasingly operating as the country's main military and political force, seem to be bracing themselves for a showdown if the Iranian-Saudi conflict worsens and spreads into Iraq.
Worse still, increased friction between the two regional rivals could shake up Iraq's fragile political landscape.
The rupture between Iran and Saudi Arabia comes at a delicate moment in the fledgling effort to launch a badly needed and US-backed political process that will empower Iraqi Sunnis in the aftermath of ISIL's pushback.
The tensions would only bolster hard-liners on both sides, feeding the deepening Shia-Sunni divide and hindering, or even blocking, a badly needed reconciliation in the fight against ISIL and efforts to bring stability back to Iraq.
Even if the political outrage over the execution of the Saudi Shia leader begins to fade somehow, tensions between Iran and Saudi Arabia are expected to continue simmering and Baghdad will remain caught in what could turn to be an apocalyptic Middle East sectarian storm.
Source: Al Jazeera