Head of Free Syrian Army's military council says Washington is bypassing the council in sending weapons directly to groups that are hard to control

* Moderate rebel commander warns of emerging warlords

* Says could fuel Somali- or Afghan-style instability

* U.S. has pledged more support for moderate rebels

By Dasha Afanasieva

ISTANBUL, June 9 (Reuters) - U.S. arms supplies to Syrian rebels may create Somali-style warlords and are undermining Washington's allies in the rebels' exile military command, the former Syrian army general who leads it said.

Brigadier General Abdelilah al-Bashir, who defected in 2012 and led rebel Free Syrian Army (FSA) forces in the Golan before becoming chief-of-staff of the FSA's Supreme Military Council in February, told Reuters that Washington was bypassing the SMC in sending weapons directly to groups that were hard to control.

"The Americans are leading the distribution of weapons on the northern front and in the southern front. We demand that we be responsible," Bashir, 56, said in an interview in Istanbul.

"Providing support to individual battalions could turn the commanders of these battalions into warlords and they will be difficult to control in future," he added.

"This could turn Syria into Afghanistan or Somalia."

His remarks echoed former U.N. envoy Lakhdar Brahimi, who compared Syria to both those countries at the weekend and warned there would be "warlords all over the place".

The U.S. State Department responded to Bashir's complaints by saying that military aid was being distributed to "moderate, vetted groups ... in coordination with" the SMC.

Formally, the U.S. supplies are "non-lethal" - such as radios, trucks and training. But some U.S. officials have told Reuters small arms and anti-tank missiles are also being given.

Bashir, whose organisation has long been dismissed by many rebels as ineffective, said Washington had sidelined it since an SMC arms depot was seized by Islamists in December. That led to the dismissal of Bashir's predecessor and to his own appointment - a promotion Bashir himself learned of only from television.

ANTI-AIRCRAFT WEAPONS

He called on the United States also to supply anti-aircraft weapons - something Washington has repeatedly ruled out for fear they could fall into hostile hands - and said that under his leadership the SMC could be trusted to monitor their use.

Describing last week's re-election of Syrian President Bashar al-Assad as "theatre", Bashir said anti-aircraft weapons would let the rebels turn the tide of the three-year-old war.

But the presence of anti-Western Islamists among the rebels means the United States and its European allies are wary of supplying arms that could be used against their own interests.

A U.S. State Department official noted that President Barack Obama promised more support to the rebels last month and said that the SMC remained involved in the process.

"As part of the State Department's provision of non-lethal assistance to moderate, vetted groups, we regularly meet and engage with the SMC and Bashir," the official said. "We are stepping up the pace of deliveries of non-lethal assistance to Free Syrian Army commanders in coordination with the SMC."

(Additional reporting by Arshad Mohammed and Mark Hosenball in Washington; Editing by Nick Tattersall and Alastair Macdonald)

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