In this January 31, 2014 file photo released by the United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA), shows residents of the besieged Palestinian camp of Yarmouk, queuing to receive food supplies, in Damascus, Syria. That year, the U.N. was able to deliver food to about five percent of people in besieged areas including Yarmouk, while today estimates show the organization is reaching less than one percent. (Photo by UNRWA via AP Photo)





A boy walks holding a rabbit beside damaged buildings in Aleppo December 31, 2014. Picture taken December 31, 2014. (Photo by Hamid Khatib/Reuters)





Abu Jasem feeds a rabbit in Aleppo January 1, 2015. A resident of Aleppo, Jasem, started taking care of animals amid debri of damaged buildings fearing a seige from forces loyal to Syria's president Bashar Al-Assad on the city, he said. (Photo by Hamid Khatib/Reuters)





Birds stand amid damaged buildings in Aleppo January 1, 2015. (Photo by Hamid Khatib/Reuters)





A boy rides a bicycle beside geese in Aleppo January 1, 2015. (Photo by Hamid Khatib/Reuters)





Residents walk beside damaged buildings in Aleppo December 31, 2014. Picture taken December 31, 2014. (Photo by Hamid Khatib/Reuters)





A man walks beside fresh produce for sale in front of a damaged building in Aleppo December 31, 2014. (Photo by Hamid Khatib/Reuters)





Free Syrian Army fighters eat their meal in Old Aleppo January 1, 2015. (Photo by Abdalrhman Ismail/Reuters)





A Free Syrian Army fighter combs his hair in Old Aleppo January 1, 2015. (Photo by Abdalrhman Ismail/Reuters)





Free Syrian Army fighters prepare their weapons in Old Aleppo January 1, 2015. (Photo by Abdalrhman Ismail/Reuters)





Civilians take pictures of themselves at the damaged al-Halwaniyeh roundabout in Aleppo January 2, 2015. (Photo by Hosam Katan/Reuters)





A woman walks with children as they look at a site hit by what activists say was a missile fired last night by forces loyal to Syria's President Bashar al-Assad in Aleppo's al-Bayyada neighbourhood January 2, 2015. (Photo by Jalal Al-Mamo/Reuters)





Fruits and vegetables are displayed for sale in front of damaged buildings in the rebel-held area of Aleppo's al-Shaar neighbourhood January 2, 2015. (Photo by Hosam Katan/Reuters)





A general view shows a street in a rebel-held area of Aleppo January 2, 2015. (Photo by Nour Kelze/Reuters)





A girl sits under a whiteboard inside a school in Old Aleppo January 3, 2015. (Photo by Jalal Al-Mamo/Reuters)





Children play on a street in Old Aleppo January 3, 2015. (Photo by Nour Kelze/Reuters)





A man carrying a child walks down a street in Old Aleppo January 3, 2015. (Photo by Nour Kelze/Reuters)





Free Syrian Army fighters launch a weapon towards the forces of Syria's President Bashar al-Assad in Ain Tarma, in Eastern Ghouta, a suburb of Damascus January 3, 2015. (Photo by Msallam Abd Albaset/Reuters)





A Free Syrian Army fighter carries a mortar shell in Ain Tarma, in Eastern Ghouta, a suburb of Damascus January 3, 2015. (Photo by Msallam Abd Albaset/Reuters)





Smoke rises from damaged buildings during what activists said were clashes between Free Syrian Army fighters and the forces of Syria's President Bashar al-Assad in Jobar, a suburb of Damascus January 4, 2015. (Photo by Msallam Abd Albaset/Reuters)





A youth sits with a blood-soaked bandage around his face at a field hospital after what activists said was an air strike by the forces of Syria's President Bashar al-Assad in the Duma neighbourhood of Damascus January 4, 2015. (Photo by Badra Mamet/Reuters)





A Free Syrian Army fighter sits behind sandbags in Jobar, a suburb of Damascus January 4, 2015. (Photo by Msallam Abd Albaset/Reuters)





Free Syrian Army fighters walk with their weapons as smoke rises in the distance in Jobar, a suburb of Damascus January 4, 2015. (Photo by Msallam Abd Albaset/Reuters)





Residents make their way over debris at a site hit by what activists said was an air strike by the forces of Syria's President Bashar al-Assad in the Duma neighbourhood of Damascus January 4, 2015. (Photo by Badra Mamet/Reuters)





A man holds a bandage to his head at a field hospital after being injured in what activists said was an air strike by the forces of Syria's President Bashar al-Assad in the Duma neighbourhood of Damascus January 4, 2015. (Photo by Badra Mamet/Reuters)





The damaged Borj al-Mualimeen building that overlooks the al-Abassin bus station is seen in Jobar, a suburb of Damascus January 4, 2015. (Photo by Msallam Abd Albaset/Reuters)





Umm Mohamad (L), a masters graduate and commander of the all-female Mother Aisha battalion, hands a box of medical supplies to a fellow member of the battalion near a field hospital in Aleppo January 3, 2015. The Mother Aisha battalion, controlled by the Free Syrian Army, provides aid and security in addition to being a full military unit. The women who make up this force not only operate as fighters on the Old Aleppo frontline, but are also in charge of two field hospitals for injured fighters and a police station for women detainees. (Photo by Abdalrhman Ismail/Reuters)





A man walks through a damaged street beside a frontline in Old Aleppo January 4, 2015. (Photo by Hosam Katan/Reuters)





A view of a frontline is seen through a damaged house in Old Aleppo January 4, 2015. (Photo by Hosam Katan/Reuters)





A rebel fighter uses his mobile phone beside barriers at a frontline in Old Aleppo January 4, 2015. The text on the flag reads, “There is no God but Allah, The Islamic Front, A nation project”. (Photo by Hosam Katan/Reuters)





A view of a frontline is seen through a hole in the wall in Old Aleppo January 4, 2015. (Photo by Hosam Katan/Reuters)





Rebel fighters carry their weapons as they stand at al-Breij frontline, after what they said was an advance in the area by them and they took control of factories where forces loyal to Syria's President Bashar al-Assad were stationed, in Aleppo January 5, 2015. (Photo by Hosam Katan/Reuters)





Rebel fighters take positions as they aim their weapons at al-Breij frontline, after what they said was an advance by them in the area and they took control of 2 factories and several buildings where forces loyal to Syria's President Bashar al-Assad were stationed, in Aleppo January 5, 2015. (Photo by Hosam Katan/Reuters)





Rebel fighters sleep inside a room at al-Breij frontline, after what they said was an advance by them in the area and they took control of 2 factories and several buildings where forces loyal to Syria's President Bashar al-Assad were stationed, in Aleppo January 5, 2015. (Photo by Hosam Katan/Reuters)





Rebel fighters warm themselves around a fire as they rest at al-Breij frontline, after what they said an advance by them in the area and they took control of 2 factories and several buildings where forces loyal to Syria's President Bashar al-Assad were stationed, in Aleppo January 5, 2015. (Photo by Hosam Katan/Reuters)





A rebel fighter stands near a factory at al-Breij frontline, after what they said was an advance by them in the area and they took control of two factories and several buildings where forces loyal to Syria's President Bashar al-Assad were stationed, in Aleppo January 5, 2015. (Photo by Hosam Katan/Reuters)





A rebel fighter receives a shave from a barber in Karm al-Jabal neighborhood of Aleppo January 5, 2015. (Photo by Mahmoud Hebbo/Reuters)





Baby strollers are seen near the debris of damaged buildings in Jobar, a suburb of Damascus, January 5, 2015. (Photo by Diaa Al-Din/Reuters)





A woman collects objects from damaged buildings in Jobar, a suburb of Damascus, January 5, 2015. (Photo by Diaa Al-Din/Reuters)





Rebel fighters carry their weapons as they move to their positions at the al-Breij frontline, after what they said was an advance by them in the al-Manasher and al-Majbal areas, where forces loyal to Syria's President Bashar al-Assad were stationed, in Aleppo January 5, 2015. (Photo by Abdalghne Karoof/Reuters)





Rebel fighters take positions as one of them peers out from behind a wall at al-Breij frontline, after what they said was an advance by them in al-Manasher and al-Majbal areas where forces loyal to Syria's President Bashar al-Assad were stationed, in Aleppo January 5, 2015. (Photo by Abdalghne Karoof/Reuters)





A general view shows a street in a rebel-held area of Aleppo January 6, 2015. (Photo by Jalal Al-Mamo/Reuters)





Civilians walk along a deserted street in the old city of Aleppo January 6, 2015. (Photo by Jalal Al-Mamo/Reuters)





Rebel fighters fire a weapon on the al-Breij frontline, after what they said was an advance by them in the Manasher al-Hajr area where the forces of Syria's President Bashar al-Assad were stationed, in Aleppo January 7, 2015. (Photo by Hosam Katan/Reuters)





A Syrian refugee girl stands behind a door at a makeshift settlement in the village of Ketermaya, south of Beirut January 8, 2015. (Photo by Ali Hashisho/Reuters)





A Syrian refugee girl carries bags of bread at a makeshift settlement in the village of Ketermaya, south of Beirut January 8, 2015. (Photo by Ali Hashisho/Reuters)





Children warm themselves around a fire in al-Sukari neighborhood of Aleppo January 8, 2015. (Photo by Hosam Katan/Reuters)





A rebel fighter pets a dog as a fellow fighter watches near the frontline against forces loyal to Syria's President Bashar al-Assad in Aleppo January 8, 2015. (Photo by Jalal Al-Mamo/Reuters)





A boy collects firewood amid graves damaged by what activists said were barrel bombs dropped by forces loyal to Syria's President Bashar al-Assad in Old Aleppo's Kadi Askar area January 9, 2015. (Photo by Mahmoud Hebbo/Reuters)





In this Wednesday, September 11, 2013 file photo, a Syrian refugee woman smokes a cigarette outside of her tent at a temporary refugee camp, in the eastern Lebanese town of al-Faour in the Bekaa valley, near the border with Syria. (Photo by Nariman El-Mofty/AP Photo)





Kurdish men sit near bonfire near a destroyed building, in the Syrian Kurdish town of Kobane, also known as Ain al-Arab, on March 22, 2015. (Photo by Yasin Akgul/AFP Photo)





Kurdish Syrian girls are pictured among destroyed buildings in the Syrian Kurdish town of Kobane, also known as Ain al-Arab, on March 22, 2015. (Photo by Yasin Akgul/AFP Photo)