The United Nations says humanitarian agencies have asked permission for inter-agency land convoys to reach 1.2 million Syrians in urgent need of aid. It says the organizations must ensure that they are out of mortal danger before attempting to deliver relief packages in besieged communities.

"We have been mobilising and stockpiling, readying ourselves for this great opportunity, great opportunity to deliver this very urgent aid but we need that peace to be reinstated before we can go in," Jens Laerke, spokesperson of Office of The Coordination for Humanitarian Affairs, said.

"We will do whatever we can to support an early restoration of the cessation of hostilities. The most critical test for this plan will be its ability to make a real difference in the life of Syrians on the ground," Jessy Chahine, spokesperson of Office of The Special Envoy for Syria, said.