DAMASCUS, The Al-Qaida-linked Nusra Front is becoming increasingly isolated, as several rebel groups are jumping ship and joining the powerful Turkish-backed Ahrar al-Sham rebel grouping, engaging in battles against the terrorist-designated militia.

The rebel infighting, sporadic in the past, intensified following an agreement between Turkey and Russia on the necessity to separate rebels from the terrorist-labeled groups such as Nusra and the Daesh.

Nusra's ties with al-Qaida have harmed it rather than benefited it as it became designated a terrorist group by the United Nations.

As Russia, Turkey and Iran agreed to a cease-fire in Syria, and further steps are expected in order to resolve the conflict, it became necessary for the rebels to distance themselves from the Nusra Front, which changed its name last year to Jabhat Fateh al-Sham, or the Front for Conquering the Levant, to divert attention from its links with al-Qaida.

However, the attempt, and Nusra's claims to have severed its ties with al-Qaida, didn't resonate positively with the international community, which interpreted the announcement as another deceptive bid.

On Thursday, five rebel groups of around 10,000 fighters, announced their allegiance to and merger with the Turkish-backed Ahrar al-Sham Movement in northern Syria, a move welcomed by the latter.

The merger comes as the Nusra Front recently started pre-emptively attacking other rebel groups in the northwestern province of Idlib, after Russia, Turkey and Iran agreed during the Astana talks this week on the need to continue fighting Nusra and Daesh.

The Astana talks grouped representatives from the Turkish-backed rebels and the Russian-backed Syrian government.

It was deemed as a breakthrough in the talks as both warring sides met for the first time face to face under the auspices of their supporters.

At the end of the conference, the rebels and the government agreed to consolidate a cease-fire, in place in Syria under the guarantees of Turkey and Russia since Dec.30, which excludes Nusra and IS, in addition to the necessity of fighting the terrorist groups.

Swiftly, clashes flared in Idlib, where Nusra is heatedly trying to claim more territory before other rebels can prepare themselves for an assault against it.

A military expert, who requested anonymity, told Xinhua that the rebel infighting, after more rebels joined Ahrar al-Sham, will further intensify in the next days between Turkish-supported Ahrar al-Sham and Nusra, which were allegedly backed by Saudi Arabia and other Gulf states.

The expert said Nusra's powerful supporters will back them "till the end."

No representatives from Gulf states attended the Astana talks.

Labib al-Nahas, one of Ahrar al-Sham's commanders, implied in several tweets recently that battles will flare up between Ahrar al-Sham and the Nusra Front.

However, thwarting Saudi Arabia's role in the Syrian war will be a daunting task for the Turkey-backed rebels, as Nusra remains a powerful nemesis.

Nusra managed to destroy over 13 rebel groups in the past two years, reminiscent of Afghanistan's Taliban Movement, which eradicated other jihadi groups fighting with it against the Soviets for the sole purpose of becoming the largest and most powerful group in control.

Nusra also began with alliances with similar groups, only to liquidate its previous allies.

Nusra's first targets were the smaller rebel groups, and currently the time has come for its major confrontation with Ahrar al-Sham, or an all-out confrontation in Idlib, the major rebels groups' main stronghold.

According to reports from Idlib, the war has already started.

The rebel-against-rebel battles and the emergence of some other groups, may eventually facilitate negotiations toward resolving the crisis.

Instead of the dozens of decentralized rebel groups active now, only one or two rebel groups will be at the the negotiation table in the future, making it easier translate their decisions and pledges on the ground.

As for the struggle against Daesh, Turkey and Russia have recently joined forces, for the first time, and started striking Daesh positions in northern Syria.

Meanwhile, a U.S.-led coalition is also expected to play a more serious role against IS, under the administration of President Donald Trump.

Trump was very clear about his desire to liquidate terrorist groups in Syria. The policies of his predecessor, Barack Obama, on the Syrian conflict and on terrorist groups in Syria were seen ambiguous.