A new military alliance of rebel groups in northern Syria aims to consolidate military control over Idlib province, the western part of Aleppo province and parts of Latakia province, according to a Free Syrian Army (FSA) commander.

Two sources from FSA have confirmed to Al Jazeera that the new military operation room, under discussion, will be supported by the "Friends of Syria" - a coalition of the US, Turkey, Western European and Gulf states - which have supported the Northern Front's operations room, known by its Turkish acronym MOM.

The commander said that the rebel forces will fight against the Syrian regime in northern Syria. He denied media reports that their goal would be to attack Hay'et Tahrir al-Sham, a Salafist alliance dominated by Jabhat Fatah al-Sham (JFS, formerly known as al-Nusra Front) which formally renounced its affiliation to al-Qaeda in 2016.

The FSA commander confirmed that the funding and logistical support for rebel factions in northern Syria which the CIA froze in February have been restored to a certain extent.

Another FSA source told Al Jazeera that Turkey and the US are still to decide what form the new rebel command will assume and added that pressure is exerted on other rebel factions to join it. He also said that in January the CIA told FSA factions it was funding not to join the Moscow-sponsored Astana talks in which Turkey participated along with Russia, Iran and the Syrian regime. High-level US officials did not attend the talks.

READ MORE: The battle for Raqqa explained

The FSA is a loose umbrella of what are seen as moderate rebel groups. Previous attempts to establish unified command failed as the FSA succumbed to factionalism and internal disagreements.

Among the groups joining the new formation are Failaq al-Sham as well as FSA-affiliated Tajamo Fastaqim, Jaish al-Mujahideen and Jaish Idlib. Fadlallah Haji from Failaq al-Sham has been chosen as its leader.

In January, a number of these groups, including Tajamo Fastaqim and Jaish al-Mujahideen, joined the ranks of the influential Islamist Ahrar al-Sham movement seeking its protection from attacks by JFS.

While ِAhrar al-Sham has not yet clarified its position on the newly formed unified command, according to Syrian analyst Ahmad Aba Zeid, those factions will continue their association with the movement.

Syrian analyst Mohamed al-Abdullah told Al Jazeera that Ahrar al-Sham might be a key factor in the success of the unified command.

"Ahrar al-Sham will be the factor making or breaking this unification. If Ahrar al-Sham refuses to join, I don't think this [unification attempt] will be successful. As we all know, Ahrar al-Sham is the main military force in the region," he said.

Abdullah also explained that the rebel factions do not have much of a choice about joining the new operations room and that not doing so would mean a confrontation with the US.

The move to unify rebel factions in northern Syria came just a few days after US Secretary of State Rex Tillerson visited Turkey. Earlier last week, Turkish Prime Minister Binali Yildirim announced the end of Turkey's Euphrates Shield operation in Syria, suggesting there might be future operations with Turkish involvement in Syria.

According to Aba Zeid, it is possible that the new unified command is part of negotiations between the US and Turkey in which the participation of Turkish-backed Syrian forces in the battle for Raqqa is also on the table.

Ankara and Washington have disagreed on how to proceed with the anti-ISIL operation in Syria and specifically the capturing of Raqqa. Turkey has protested US support for the Syrian Democratic Forces (SDF) and their likely alliance for the battle for Raqqa. Ankara considers the Kurdish People's Protection Units (YPG), which dominates the SDF, a "terrorist" organisation and has argued that Kurdish domination of Raqqa would be problematic for the majority of Arab residents of the city.

OPINION: Implications for a Syrian transition under Assad

In March, US troops were deployed in Manbij, east of the territory controlled by Turkish forces and their FSA allies in northern Syria, in order to stop their progress eastward and prevent clashes with the SDF.

Abdul Majeed Barakat, political adviser of FSA forces which were included in the Euphrates Shield operation, told Al Jazeera that Turkey had planned a unified rebel army under the name "Al Jaish Al Watani" or "Jaish Al Tahrir". That force was supposed to lead a second phase of Turkey's operations in Syria which was to focus on Idlib province. Barakat said that a number of meetings were held in Ankara between the Turkish authorities and rebel commanders to discuss the issue.

According to the FSA commander, an agreement could not be reached on how to form an army out of all the factions that participated in the meetings and, therefore, the decision was made to have a unified command under the support of the MOM.