Ambulances gather at a site that was hit by what activists said was an air raid by forces loyal to Syrian President Bashar al-Assad in the Duma neighbourhood of Damascus on Dec. 12. (MOHAMED ABDULLAH/REUTERS)

The Obama administration is willing to consider supporting an expanded Syrian rebel coalition that would include Islamist groups, provided the groups are not allied with al-Qaeda and agree to support upcoming peace talks in Geneva, a senior U.S. official said Thursday.

In addition, the official said, the Americans would like the Islamic Front groups to return U.S. vehicles, communications gear and other non-lethal equipment they seized last weekend from warehouses at the Syria-Turkey border.

The seized material, which had been provided to the U.S.-backed Supreme Military Council (SMC) of Syrian opposition fighters, led the administration this week to suspend aid shipments through Turkey.

The emergence last month of the Islamic Front has presented the administration with a dilemma as it seeks to maintain military pressure on the Syrian government before an opposition-government peace conference next month that it hopes will lead to the ouster of President Bashar al-Assad and the installation of a transitional government.

The SMC, whose Free Syrian Army is the only opposition armed force the United States backs in Syria, has lost both strength and influence to anti-
Assad Islamic groups. Among them is the al-Qaeda-affiliated Islamic State of Iraq and Syria and the al-Nusra Front, both of which have been labeled terrorist groups by Washington.

But the increasingly powerful Islamic Front, while it includes many Salafists seeking an Islamic state in Syria, is not affiliated with al-Qaeda. Talks between U.S. envoy Robert Ford and Islamic Front figures held in Turkey last month were inconclusive, said the senior U.S. official, who spoke on the condition of anonymity about the developing policy.

The Front has been pressing for inclusion in the SMC, and wants to be represented at the Geneva talks, according to rebel commanders. Front leaders are reportedly in discussions this week with the SMC commander, Gen. Salim Idriss.

Ford is traveling to London on Friday to meet with other international backers of the Syrian opposition, and then to Turkey for discussions with the Syrian ­Opposition Coalition, the U.S.-
backed political leadership. He may also meet there with the Islamic Front, said the senior official.

“We don’t have a problem with the Islamic Front,” the official said, but any movement toward including them in the U.S.-backed coalition remains a “work in progress.”

In addition to the absence of any al-Qaeda ties, the administration is seeking assurances from the Front that it will support the Syrian Opposition Coalition’s leadership in the Geneva conference, scheduled for Jan. 22.

But “whatever happens with the reorganization” of the armed opposition, the official said, “we want our stuff back.” The equipment, including vehicles and communications and medical equipment, was part of a program, administered by the State Department, to send U.S. non-
lethal supplies to the SMC. A separate program, run by the CIA, distributes small arms and ammunition to the rebels.

The cluster of warehouses in the Syrian border town of Atmeh was controlled by the SMC, and it is unclear how it ended up in Islamic Front hands.

By one account, the Islamic Front offered to help SMC fighters defend the site from an anticipated attack by a group linked to al-Qaeda, and then ejected the SMC rebels at gunpoint.

“We’re not in a position yet to give a definitive account of what happened,” State Department spokeswoman Marie Harf said Thursday. Clarifying earlier reports that Idriss was present at the warehouses and fled from Islamic Front forces, Harf said that he is currently in Turkey, and was in that country at the time of the weekend incident.

Harf emphasized that the flow of non-lethal military aid continued to flow into Syria through other countries. Other than Turkey — on Syria’s northern border, where much of the heaviest fighting is now underway — the primary route is through Jordan, in the south.

Britain also announced it was suspending non-lethal aid deliveries to the SMC through Turkey.

The suspensions do not affect humanitarian aid to Syria.