Obama signs covert action backing Syrian rebels: Reports

WASHINGTON (AFP) - President Barack Obama has signed a covert document authorising United States (US) support for Syrian rebels locked in a battle to overthrow beleaguered President Bashar al-Assad, reports said on Wednesday.

The directive was contained in a "finding" - a device authorising clandestine action by the Central Intelligence Agency, NBC and CNN said, citing unidentified sources.

White House officials declined to comment on the reports but did not specifically rule out the idea that Washington was providing more intelligence support to anti-Assad forces than had previously been made public.

Washington has previously said that it is offering medical and communications assistance to Syrian rebels but declined to supply arms, warning it would be counter-productive to further "weaponise" the conflict.