A man stands atop a damaged building as he takes pictures of ambulances and buses evacuating people and driving out of a rebel-held part of Aleppo, Syria December 15, 2016. REUTERS/Omar Sanadiki

RIYADH (Reuters) - A senior Syrian opposition figure called on Thursday for an increase in Gulf Arab military support for armed rebels following the fall of the city of Aleppo to government forces this week.

The loss of the rebels’ last urban stronghold this week has dealt a devastating blow to efforts to oust President Bashar al-Assad, after nearly six years of a war that has claimed some 400,000 lives and left 11 million people homeless.

“The support has not changed,” said Asaad al-Zoubi, chief negotiator for the main opposition body, the High Negotiations Council, who is based in Saudi Arabia.

“I would like and I request for there to be an increase in support. The present situation requires additional support,” he told Reuters, citing a need for specialized weapons that the United States has blocked Gulf partners from delivering.

The fall of Aleppo has also handed a major victory to Iran, whom the rebels’ Gulf Arab backers see as their main foe in the battle for regional influence.

Another rebel backer, Turkey, has indicated that its support for the rebel brigades is far from over. It is redeploying fighters from Aleppo to Syria’s north to join a campaign to drive Islamic State and Kurdish militia fighters away from the Turkish border.