The United States has stopped nonlethal aid to northern Syria after the Islamic front seized a supply warehouse and headquarters facility of the Supreme Military Council, the U.S.-backed moderate opposition military group.

"We're obviously concerned that Islamic Front forces have seized the Atmeh headquarters and warehouses belonging to the SMC, and we are, of course, in close contact with General Idris and the SMC about these events," State Department spokeswoman Jen Psaki said at today's daily press briefing. "We're gathering the facts, consulting with friends in the Syrian opposition on the next steps we can do in support of the Syrian people."

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The State Department is now in touch with the council to "inventory" what was in the warehouse and is "working closely" with Supreme Military Council leader Gen. Salim Idris.

"We're, of course, evaluating what was included in there," Psaki said, noting that it would have included things like meal kits and laptops.

The move will only affect aid to Syrian rebels, not humanitarian aid to the Syrian people, Psaki said.

"Humanitarian assistance is distributed, as you all know, through international nongovernment organizations, including the U.N., and that is not impacted. That assistance is not impacted by this," Psaki said today.

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The United States and allies have sought to bolster the SMC, the command network for Gen. Idris' Free Syrian Army, as Syria's "moderate opposition" over other groups, announcing $500 million in nonlethal support in April.

The State Department confirmed last week that it has been talking to "some Islamist groups" in Syria, and while Psaki wouldn't confirm today that the United States is talking to the Islamic Front - an umbrella coalition announced last month, as The New York Times reported, that is reportedly the largest rebel group in Syria - she reiterated that the United States is engaged with a "broad cross-section of Syrian people and political and military leaders."

The Islamic Front is not the same as two other Islamist militias operating in Syria, the al-Nusra front and the al Qaeda offshoot ISIS (Islamic State of Iraq and Syria).