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Obama authorizes secret US support for Syrian rebels

Before Syrian reinforcement troops can reach Aleppo, the nation's largest city and commercial capital, they are being attacked by rebel forces in Arihah, a city situated on a key route. NBC's Richard Engel reports.

Updated at 8:14 a.m. ET: President Barack Obama has signed a so-called "intelligence finding" authorizing covert aid to the Syrian rebels seeking to depose Syrian President Bashar al-Assad and his government, NBC News has confirmed.

White House and intelligence officials declined to comment on a Reuters report about the aid.

A U.S. official also said that while Secretary of State Hillary Clinton has said the U.S., is providing non-lethal aid and communications to the rebels, the presidential finding provides more intelligence resources than had been previously known.

The administration has been under constant criticism for months from Sen. John McCain, R-Ariz., and others who say the administration should be arming the rebels.

Saudis mum on aid center for Syrian rebels

Obama's order, approved earlier this year, broadly permits the CIA and other U.S. agencies to provide support that could help the rebels oust Assad, Reuters reported.

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People resisting the army of President Bashar al-Assad in northern Syria cope with loss and prepare for fighting.

This and other developments signal a shift toward growing, albeit still circumscribed, support for Assad's armed opponents -- a shift that intensified following last month's failure of the U.N. Security Council to agree on tougher sanctions against the Damascus government, Reuters reported.

UN: Syria using fighter jets against rebels with tanks

The White House is for now apparently stopping short of giving the rebels lethal weapons, even as some U.S. allies do that, Reuters said.

But U.S. and European officials have said that there have been noticeable improvements in the coherence and effectiveness of Syrian rebel groups in the past few weeks. That represents a significant change in assessments of the rebels by Western officials, who previously characterized Assad's opponents as a disorganized, almost chaotic, rabble, Reuters reported.

Precisely when Obama signed the secret intelligence authorization, an action not previously reported, could not be determined, Reuters said.

Residents face shortages as Syrian army hits Aleppo 

The full extent of clandestine support that agencies like the CIA might be providing also is unclear, Reuters said.

For days the Syrian troops' weapons have given them the upper hand during key battles in Aleppo, but the rebels – now armed with powerful shoulder fired anti-aircraft missiles -- are preparing for a different kind of fight. NBC's Richard Engel reports.

White House spokesman Tommy Vietor declined comment to Reuters.

A U.S. government source acknowledged that under provisions of the presidential finding, the United States was collaborating with a secret command center operated by Turkey and its allies.

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Last week, Reuters reported that, along with Saudi Arabia and Qatar, Turkey had established a secret base near the Syrian border to help direct vital military and communications support to Assad's opponents.

This "nerve center" is in Adana, a city in southern Turkey about 60 miles from the Syrian border, which is also home to Incirlik, a U.S. air base where U.S. military and intelligence agencies maintain a substantial presence.

This article includes reporting by NBC News' Andrea Mitchell and Reuters.

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