Beirut: In a war-battered suburb of Damascus, a commander for one of the smaller nationalist brigades fighting to topple Syrian President Bashar Al Assad grumbles about the lack of ammunition for his men. He blames Qatar, saying the oil-rich Gulf state directs its backing to rebels with a more Islamist ideology.

Tiny, US-allied Qatar has emerged as one of the strongest international backers of the rebellion against Syrian President Bashar Al Assad. Many in the Syrian opposition laud Qatar, saying it has stepped in while the international community has failed to intervene or send military aid that would help tip the balance in favour of the rebels, three years into the uprising-turned civil war that has ravaged the country and killed more than 70,000 people.

But its role has also caused tensions within the ranks of the highly fragmented rebellion and political opposition. Some rebel brigades complain they are left out in the cold from the flow of money and weapons, sparking rivalries between secular and Islamist groups. Fighters and opposition activists worry that Qatar is buying outsized influence in post-Al Assad Syria and giving a boost to Islamist-minded groups if the regime falls.

“Qatar is working to establish an Islamic state in Syria,” Abu Ziad, the commander of a brigade in the Damascus suburb, said sullenly, his Kalashnikov rifle resting on a wooden chair next to his tea glass.

“With their money, the Qataris and a bunch of other countries are exploiting the Syrian revolution, each for their own gains,” said Abu Ziad, speaking on condition he be identified by his nom de guerre for fear of reprisals from the Syrian regime.

Qatar is not the only country in the region feeding support to the rebellion, and the various lines of backing have prompted worries that numerous countries are trying to win influence, often with conflicting agendas. No country has revealed the extent of its aid to the rebellion. But Qatar appears to be the most prominent.

Officials, diplomats and Western military experts told The Associated press last month that Jordan, Saudi Arabia, Turkey and Qatar were involved in a carefully prepared covert operation of arming the rebels. The US has a consulting role aimed at ensuring the weapons go to secular and moderate rebel groups.

President Barack Obama met Tuesday at the White House with Qatar’s ruler, Emir Hamad bin Khalifa Al Thani, and said their two countries will continue to work on more support for the Syrian opposition in the coming months. Washington says it is providing non-lethal aid to the opposition.

US Secretary of State John Kerry acknowledged Qatar’s influential role at a joint press conference with the country’s prime minister in Doha last month. He said he had received “greater guarantees” from Qatari leaders that nearly all the arms were getting into the hands of moderates among the Syrian rebels.

Qatari officials have denied their country aims to determine the shape of a post-Al Assad government in Syria. Qatar’s prime minister, Hamad bin Jassim Al Thani, sought to downplay his country’s image as the chief Arab patron for the opposition and dispel worries that it seeks to dominate the scene.

“We are not looking for a role just for us,” he told reporters at the time. “We are looking for a pan-Arab role.”

Syrian opposition figures regularly complain that the main opposition umbrella group, the Syrian National Coalition, is dominated by fundamentalists from the Muslim Brotherhood backed by Qatar.

Last month, the coalition elected American-educated Ghassan Hitto as its prime minister but almost immediately witnessed a walkout by about a dozen of its members, who accused Qatar and the Brotherhood of using pressure to install its candidate for prime minister.

“The new (interim) government will be composed by the government of Qatar and we will not be part of it,” said well-known opposition figure Kamal Al Labwani, who suspended his membership from the coalition.

Several rebel officials and opposition activists said Islamist rebel brigades backed by Qatar are getting the bulk of the weapons. They spoke on condition of anonymity to talk about the clandestine flow of support.

The majority of rebel factions in Syria have religious leanings to some degree, and many of them call for some sort of rule by Islamic law in a post-Al Assad era. The Qatari support does not appear to be going to the most hard-line militant or ultraconservative fighters, such as Al Qaida-linked Jabhat Al Nusra, but rather toward organizations with a conservative religious ideology, away from brigades with a secular or nationalist bent.

Among those are Islamic groups such as the Ahfad Al Rasoul, Al Furqan and Tawheed brigades, the rebel officials and activists said. Tahweed is one of the largest rebel groups operating in the northern province of Aleppo, which has been a major front in the civil war since July. It is also strongly backed by the Muslim Brotherhood, the fundamentalist political organization that is closely allied to Qatar, and is part of the Syrian Islamic Liberation Front, an umbrella group formed last year incorporating some of the largest Islamist groups in northern Syria.

Representatives of those brigades could not be reached for comment.

A senior member of the Military Council in Damascus and its Suburbs, which is seen as a moderate Islamic faction, said his group’s fighters do not receive weapons but that the “brothers” in Qatar were among the chief financers of the group. He spoke on condition of anonymity for security reasons.

The Military Council nominally falls under the main rebel umbrella Free Syrian Army. The FSA regrouped in December under a unified rebel command headed by Gen. Salim Idris, who is seen as a secular-minded moderate. But Idris is believed to have very limited control over the dozens of brigades and battalions inside Syria.

Abu Ziad said tensions resulting from diverging allegiances among rebel factions have led to setbacks on the ground. He cited the case of Jobar, a key district on the northeastern edge of Damascus, where rebels have been trying to push in the capital and clashing with government troops for weeks.

The area is controlled by nationalist brigades including his own, Islamist groups backed by Qatar and Saudi Arabia and Jabhat Al Nusra. But the rebels’ advance in the district has been held up by disagreements between the groups over who should take the lead in the fight, he said. His account of the situation was corroborated by two other rebels, who spoke on condition of anonymity to discuss the divisions among fighters.

“My men have been in Jobar for 55 days with hardly any ammunition,” said Abu Ziad. He said Islamic factions recently received shipments that “they do not share.”

There is also mistrust of Qatar on the opposite end of the rebel spectrum, among the more hard-line Islamic fighters.

Abu Mohammad, a fighter for Ahrar Al Sham, a prominent rebel brigade in northern Syria with an ultra-conservative ideology, said Qatar, as well as Turkey, “is interested in ruling Syria” once the regime is toppled.

He said his group never saw “a dime from Qatar, which supports its own people.” He declined to specify which groups Qatar backs. He spoke via Skype from the eastern city of Raqqa, which in early March became the first provincial capital to completely fall to the rebellion and which is now controlled by Ahrar Al Sham and Jabhat Al Nusra.

Abu Mohammad said his group received some weapons from Iraqis and some from “good people in the region” but mainly from looting the stores of regime forces. He spoke on condition he be identified by his nom de guerre to avoid reprisals.

Qatar has strongly touted its support for the Syrian uprising. At an Arab League summit last month in Doha, Qatar managed to push through a declaration saying member states had a “right” to aid rebel fighters. The statement was seen as an attempt by Qatar to burnish its reputation in the battlefield and mark itself as a leading advocate for the various rebel forces.

Qatar was among the few Arab states offering active military assistance to NATO-led attacks against Moammar Gaddafi’s regime in Libya and, at the same time, was a key arms-and-money pipeline for Libyan rebels who overthrew Gadaffi. In Egypt, Qatar has been a strong backer of President Mohammad Mursi, a veteran of the Muslim Brotherhood.

“Qatar has something of an image problem with the rebels in the field” in Syria, said Salman Shaikh, director of The Brookings Doha Center in Qatar. “They are seen as almost pushing too hard and that raises questions about their objectives.”