A pledge of allegiance by Al-Nusra Front, a jihadist group battling Syrian President Bashar al-Assad's regime, to Al-Qaeda could backfire and undermine its hard-won support on the ground, analysts say.
The rebel group, which has spearheaded the violent uprising against Assad's forces, made the announcement in an audio message in which its leader said it was committed to Al-Qaeda chief Ayman al-Zawahiri.
The recording came shortly after Al-Qaeda's front group in Iraq said Al-Nusra Front was an offshoot of its own organisation, a claim Nusra leader Abu Mohammed al-Jawlani seemed to distance himself from in his remarks.
But the move to explicitly link the group to Al-Qaeda's global network could backfire and undermine local support for Al-Nusra Front, or Jabhat al-Nusra in Arabic, which has been credited with playing a major role in rebel gains against forces loyal to Assad, analysts told AFP.
"Jabhat al-Nusra has gained significant support within Syria because it has results, and because it has been careful not to alienate its immediate environment," said Peter Harling, a project director in International Crisis Group's Middle East Programme.
"Its vision for the future of Syria and some of its tactics are nevertheless creating serious debate and pushback on the ground. Its pledge of allegiance will mostly play against it, through association with an entity that is foreign to Syrian culture and that is seen as having failed in its prior endeavours."
Wednesday's announcement by Jawlani is likely to bolster assertions by Assad's regime that it is fighting "terrorists" who want to impose an Islamic state, and could further complicate Western attempts to help rebel forces.
"The sons of Al-Nusra Front pledge allegiance to Sheikh Ayman al-Zawahiri," Jawlani said in the recording.
In December, Washington labelled Al-Nusra Front a "terrorist" organisation, citing links to Al-Qaeda in Iraq and describing the group as "an attempt by AQI to hijack the struggles of the Syrian people for its own malign purposes".
Harling played down links between the two groups, arguing that Nusra was not an outgrowth of Al-Qaeda's Iraqi front group, but, like many other analysts, noted that fighters who gained experience in Iraq have played a major role in the group's ascent.
Nusra also appears to have learned lessons from Al-Qaeda's experience in Iraq.
Both groups achieved notoriety for their use of suicide attacks and car bombs, as opposed to the more conventional warfare of other insurgent factions in Iraq and Syria.
But Nusra insists its targets are military or part of the regime apparatus, even though its attacks have often caused civilian casualties. By contrast, Al-Qaeda in Iraq quickly gained a reputation for brutality towards civilians.
Islamism specialist Cole Bunzel said the open admission that Nusra was linked to a non-Syrian organisation appeared to be a strategic blunder.
"It emphasises the fact that Jabhat al-Nusra is a foreign entity, and it is Al-Qaeda," said Bunzel, a PhD candidate at Princeton University.
"No longer can Jabhat al-Nusra, or what it's now called, gloss that over, or deny that connection."
Whether or not the move has a tangible impact on the ground, however, Washington's move to blacklist Al-Nusra last year may have made the group's latest decision a fait accompli.
"Aligning with Al-Qaeda, I think, is a strategic mistake that will cost them dearly," said Mathieu Guidere, a specialist on jihadist groups at the University of Toulouse-Le Mirail.
But, he added, "they had no choice".
"The fact that the United States put Al-Nusra Front on the list of terrorist organisations, it is clear, pushed them into the arms of Al-Qaeda, even if it costs them."