UN humanitarian chief Mark Lowcock is visiting Syria this week to see how to improve the delivery of aid to people in besieged areas.
One of these areas is Eastern Ghouta, one of the last rebel-controlled areas on the outskirts of Damascus, which is under increasingly heavy bombardment.
Critics accuse the Syrian government of forcing people to starve or surrender, as part of a policy of forced displacement of civilians from opposition-controlled areas.
Al Jazeera's Natasha Ghoneim has more.
