US defence officials now believe that Russian planes dropped the bombs that destroyed a UN aid convoy that killed at least 20 people, the Guardian has learned.
The claim of direct Russian involvement in the bombing, if confirmed, would have far-reaching consequences.
Earlier on Tuesday, Ban Ki-moon used his farewell address to the UN generalbassembly to denounce it as a “sickening, savage and apparently deliberate attack”, describing the bombers as “cowards”, and UN officials have said it is a potential war crime.
The outgoing secretary general told world leaders in New York that the UN had been forced to suspend
aid convoys in Syria because of Monday’s attack on Syrian Red Crescent trucks that were carrying UN food supplies to a rural area west of Aleppo city.