In addition, Zawahri called on the jihadis to unite their ranks, saying “You have to unite and come together with your Muslim and jihadist brothers in Syria and in the entire world.” He also called on himself and the jihadis to practice self-revision because “it is the first step on the path of victory.” This indicates that his policy is based on opening a new page of relations between other jihadi groups, and it is proof of what Allawi’s intelligence information has revealed.

There are indications that prominent jihadi forces in the region are making plans for when IS loses ground. In this context, Zawahri urged the jihadis in an audio recording published April 23 to practice jihad and prepare themselves for a long war against whom he called “the Crusaders and their allies, the Shiites and Alawites.” He also pressed them to follow guerrilla tactics.

In line with Allawi's statement, Iraqi intelligence sources reported April 27 that prominent IS leaders have returned to Diyala province in eastern Iraq to start negotiations with remnants of al-Qaeda on forging a new alliance.

Allawi said in a press statement April 17, “Negotiations have already begun. There are discussions and dialogues between representatives of [Abu Bakr] al-Baghdadi and [Ayman] al-Zawahri," in reference to the leaders of IS and al-Qaeda, respectively. Also, Allawi added, “I can't see IS disappearing into thin air. They will remain covertly in sleeping cells, spreading their venom all over the world.”

Iraqi Vice President Ayad Allawi has revealed that al-Qaeda and the Islamic State (IS) are discussing a possible alliance. Despite their differences, rapprochement is possible between the two, especially if a change in leadership occurs in one of these groups.

It is clear that al-Qaeda sees IS’ successive losses as an opportunity to regain its role as a leader among the jihadi armed groups in the upcoming phase. IS had stolen al-Qaeda’s thunder with its military victories and announcement of the Islamic caliphate, but the recent setbacks have paved the way for al-Qaeda to play a bigger role among jihadi forces. The US Institute for the Study of War warned in February that al-Qaeda would become active again in Iraq, simultaneously as IS loses the land it had occupied there.

The differences between the two jihadi groups emerged in May 2013 when Zawahri ordered in an audio recording to “abolish IS.” Baghdadi had announced in March 2013 that he would unify the Islamic State in Iraq and Jabhat al-Nusra in Syria to establish the Islamic State in Iraq and Syria, which then became known as IS.

The differences between the two groups led them to accuse the other of treachery. A senior IS leader called Zawahri’s al-Qaeda the “Jews of Jihad.” For his part, Zawahri strongly attacked the leader of IS and accused him of stirring up strife in the ranks of the jihadis. The differences between these two groups were not limited to inciting statements, but led to military clashes.

Yet the necessities of the upcoming stage make it imperative for the leaders of these groups to consider rapprochement. The attempts to unify scattered jihadi groups are not new; al-Qaeda has succeeded in consolidating the various jihadi groups under its banner. It was much stronger than it is now because it had money and training bases in Pakistan and Afghanistan and was headed by Osama bin Laden, who had charisma, which his successor, Zawahri, lacks.

Today the picture is completely different, as IS is still stronger than al-Qaeda and more influential in the arena, despite the heavy losses it has recently endured.

However, no one can deny the great similarity in the ideology adopted by both groups, which could serve as a springboard for them to return to cooperation. In this context, Hisham al-Hashemi, an Iraqi expert on jihadi groups, told Al-Monitor, “The leaders and members of both IS and al-Qaeda believe in the same doctrine as well as they have the same resources of jurisprudence.” Both groups are committed to the principles of global jihad founded by Abdullah Azzam.

This similarity in ideology will not stop the two leaders from competing over leading the Islamic nation. Each one of them sees themselves as more deserving. Zawahri is the successor to bin Laden, but Baghdadi fits the requirement of a “vilayet.”

These differences date back to the era of Abu Musab al-Zarqawi's leadership over al-Qaeda in Iraq, who believed that legitimacy comes from the battlefield and not from above. The leaders of the two groups also disagree about the priorities of jihad at this stage. Although both share the ultimate goal of establishing the Islamic caliphate throughout the world, al-Qaeda leaders believe that this stage requires striking the distant enemy, namely the West, especially the United States, while IS remains preoccupied with the local enemy.

There are different scenarios about a possible alliance between al-Qaeda and IS, but there is no doubt that Baghdadi and other IS leaders will not operate under al-Qaeda’s umbrella, as was the case prior to the declaration of the Islamic State.

Hashemi believes that the deep-rooted differences make the rapprochement and alliance between the two groups difficult at this stage. “I do not think there is any rapprochement on the level of understanding or military and security coordination. … When one of the two leaderships fades away, only then it would be possible for one group to join the other,” he said.

However, this does not necessarily mean it would take long for one of them to fade away, since IS is fighting on several fronts simultaneously, which caused it to lose the majority of its prominent leaders. In addition, the United States had promised a $25 million reward for information about Baghdadi, and Zawahri and other al-Qaeda leaders are being pursued by the United States. If one of these leaders are killed, rapprochement between the two groups would be easier.