The denunciation of last week's mortar assault on Saudi Arabia's border came from the Media Department of Iraq's Foreign Ministry which also promised that the government will pursue the "terrorist elements" who fired the shells. Meanwhile, Prime Minister Nouri Al-Maliki's government, which holds the real power in the country, remained tight-lipped on the attack, the worst border violence since the US invasion in 2003.
Al-Maliki's discrete silence speaks volumes about the relations between Iraq and Saudi Arabia which remained tense for much of the past decade. Iraqi Shia politicians argue that the Saudi government maintains unfriendly attitudes toward its northern neighbour. They perceive that the kingdom is supportive of Iraqi Sunni Muslims, while Saudi religious extremists put Iraq's Shia high on their target list.
Indeed, only days before the mortar attack, al-Maliki held Saudi Arabia responsible for the deterioration of the relations between the two countries and accused Riyadh of supporting (Sunni) extremist groups in Iraq and fuelling the uprising against Bashar al-Assad's regime in Syria. It was the first time al-Maliki went public criticising Saudi Arabia, signalling a shift to a more open animosity toward the kingdom and showing more self-confidence in his regional diplomacy.
Iraqi Shia are thus heading into uncharted waters, driven by the realization that the Middle East will be profoundly different after the Iran nuclear deal.
A spirit of defiance
It was not a coincidence that al-Maliki, who is stumbling and unable to get things done at home, has finally got the stomach for the fight with Saudi Arabia; nor was the mortar attack on the border post in northern Saudi Arabia. The timing could not be more perfect for Baghdad to send a tough message to Riyadh, which finds itself in an uncomfortable position over a host of regional setbacks, including its failure to take Washington on board over Syria and the US diplomatic detente with Iran.
For sure, Maliki's government feels that the Western rapprochement with Iran and the window of opportunity now open for al-Assad with the Geneva-2 talks have tilted the balance of power in the Middle East towards their allies in Tehran. It hopes this will also lay out the opportunity to make Saudi Arabia - whose "muscular role" in Iraq has never been a secret - increasingly weaker. This could allow Iraqi Shia to reposition themselves, playing the so-called "pan-Shiaism" card and moving on the offensive.
Nothing can explain this better than the remarks made by Wathiq al-Battat, the leader of the Iraqi Shia militia which took responsibility for the shelling of the Saudi border post. "This is just the beginning, and there will be more attacks if [the Saudis] do not stop," he told an Iraqi television network. These words would have seemed empty rhetoric a few weeks ago, but now they should raise alarm not only in Saudi Arabia, but also in the entire Gulf, especially because we know that al-Battat's groups are seen as a facade for al-Quds Force, the influential intelligence arm of Iran's Revolutionary Guard in Iraq.
Inevitably, a nuclear deal with Iran will have vast implications on the regional balance of power. It has the potential to reshape relationships throughout the Middle East. No country will be more affected by the ensuing uncertainty than the two regional powers - Iran and Saudi Arabia. The prospect of geo-strategic rivalry between the two is expected to be on an upward trajectory, with several sources of short- and longer-term tension evident. The key element of this strategic process is the widening Shia-Sunni split engaging the two regional heavyweights and their proxies. Unfortunately, this split is perhaps most glaringly apparent in the Iraqi arena, and Iraq is expected to bear most of the adverse consequences of the competition for reach and influence in the region.
Judging by Iraqi Shia leaders' celebratory reaction to the "historic accord" snatched by Iran, they will see a glimmer of optimism that they could be finally recognized and fully accepted by Sunni Arabs, and in particular by Saudi Arabia, one of their arch adversaries. Iraqi Shia are thus heading into uncharted waters, driven by the realization that the Middle East will be profoundly different after the Iran nuclear deal. This is a region that in geopolitical terms is dominated by the inexorable rise of Iran, by the perceived threat of more empowerment of Iraqi Shia, and by the accelerating trend toward a regional Shia condominium. Iraqi Shia groups are, therefore, expected to be more aggressive in their approach toward Saudi Arabia, if the kingdom is reluctant to "surrender" to the pro-Iran camp.
Amid all this uncertainty unleashed by the Iran deal, Iraq seems to continue to be a playground for both Iran and Saudi Arabia.
New regional system
By contrast, Saudi regional power seems to be off balance largely because of the overwhelming nature of the Iran deal and the new regional order it is expected to launch. The nuclear deal is an opportunity for Iran to emerge as a single aggregation of power in the region. The Saudis' main concern is that a bigger and more comprehensive deal will enable its longstanding regional rival to forge a larger Shia alliance and use Iraq with its vast oil resources, huge Shia population, and strategic position as a linchpin to assume a superpower role in the Gulf region.
But one should not make a mistake to underestimate what Saudi Arabia, the self-proclaimed leader of Sunni Arabs, can do to counterbalance the rising Iranian influence in Iraq. As the world's largest oil exporter, Saudi Arabia can have more latitude over both Iran and Iraqi Shia, if it chooses to increase oil production and thus threaten the Iraqi and Iranian economies. Through close connections with Iraqi Sunni tribes and religious figures and its traditional checkbook diplomacy, Saudi Arabia can also wield enormous influence inside Iraq.
Nawaf Obaid, a security advisor to the Saudi royal family, recently said that the kingdom would continue to resist Iranian involvement in the region, and especially that of the Revolutionary Guards. "[Saudi Arabia] will be there to stop them wherever they are in Arab countries," he told a think tank meeting in London. These remarks by someone who usually reflects the thinking inside the royal family have only one interpretation: Saudi Arabia is ready to use its money and influence to resist Iran emerging as a regional superpower and threatening its vital national interests, including its historical self-proclaimed role as a leader of Sunni Arab Muslims.
Amid all this uncertainty unleashed by the Iran deal, Iraq seems to continue to be a playground for both Iran and Saudi Arabia. It may even sink deeper in the abyss of the sectarianism fuelled by the US invasion, which empowered Iraqi Shia, sidelined Sunnis and pushed both Muslim communities into a war of wide-ranging regional dimensions.
Salah Nasrawi is a veteran Iraqi journalist who worked for international media, including the Associated Press and the BBC in the Middle East. He wrote for leading Arab newspapers and periodicals.
The views expressed in this article are the author's own and do not necessarily reflect Al Jazeera's editorial policy.