Syrian opposition leader Riad Hijab on Tuesday accused world powers of showing "total weakness" in the face of the Syrian regime's renewed attacks and the collapse of a ceasefire.

Hijab told reporters that Russian and Syrian planes bombed an aid convoy that was en route to Aleppo to deliver food and other basic supplies to 78,000 civilians. 

"Regime and Russian planes are responsible for this attack. No one else has aircraft in that area," said Hijab, who is the coordinator of the High Negotiations Committee (HNC) seeking agreement on a political transition.

Hijab said a HNC member who was escorting the convoy had provided him with photographs of the attack that he described as "very precise."

Russia and Syria have denied any involvement in the strike on Monday that destroyed 18 trucks in the 31-vehicle convoy.

"Through this tragic incident it is the United Nations that is directly hit," Hijab said. 

"But there are no consequences. It is yet another illustration of the total weakness of the international community," he added.

The war in Syria, now in its sixth year with 300,000 dead, is dominating this week's General Assembly debate at the United Nations.

The United States and Russia, the regime's ally in the war, earlier chaired a brief meeting of the 23-nation group backing the Syrian peace process, but there was no breakthrough.

The opposition leader accused Russia of having an "exclusively military strategy" to end the war and said the international community had failed since the beginning of the conflict to recognize the seriousness of the crisis.

Source: AFP