Children press a lever to fill water containers in the rebel-held besieged Douma neighbourhood of Damascus, Syria February 15, 2017. (Photo by Bassam Khabieh/Reuters)





A boy transports water on a bicycle in the rebel-held besieged Douma neighbourhood of Damascus, Syria February 15, 2017. (Photo by Bassam Khabieh/Reuters)





A civilian herds sheep near damaged buildings in the rebel-held besieged Douma neighbourhood of Damascus, Syria February 15, 2017. (Photo by Bassam Khabieh/Reuters)





A man gets a haircut in the rebel-held besieged Douma neighbourhood of Damascus, Syria February 15, 2017. (Photo by Bassam Khabieh/Reuters)





A boy walks along a road in the rebel-held besieged Douma neighbourhood of Damascus, Syria February 15, 2017. (Photo by Bassam Khabieh/Reuters)





Children warm themselves up by standing in the sun in the rebel-held besieged Douma neighbourhood of Damascus, Syria February 15, 2017. (Photo by Bassam Khabieh/Reuters)





A youth sits inside a shop in the rebel-held besieged Douma neighbourhood of Damascus, Syria February 15, 2017. (Photo by Bassam Khabieh/Reuters)





Civilians stand in a damaged house after an airstrike in the rebel-held southern town of Bosra al-Sham, Deraa Governorate, Syria February 17, 2017. (Photo by Alaa Al-Faqir/Reuters)





A damaged house is seen after an airstrike in the rebel-held southern town of Bosra al-Sham, Deraa Governorate, Syria February 17, 2017. (Photo by Alaa Al-Faqir/Reuters)





A fighter from the Free Syrian Army's Al Majd Brigades digs a trench in the rebel held besieged area of al-Marj in the Eastern Ghouta of Damascus, Syria February 18, 2017. (Photo by Bassam Khabieh/Reuters)





A Syrian Arab Red Crescent member walks at a site hit by airstrikes in the rebel held besieged Douma neighbourhood of Damascus, Syria February 19, 2017. (Photo by Bassam Khabieh/Reuters)





Men run at a site hit by airstrikes in the rebel held besieged Douma neighbourhood of Damascus, Syria February 19, 2017. (Photo by Bassam Khabieh/Reuters)





A Syrian Democratic Forces (SDF) fighter sits in front of a damaged tower ahead of an offensive against Islamic State militants in northern Deir al-Zor province, Syria February 21, 2017. (Photo by Rodi Said/Reuters)





Syrian Democratic Forces (SDF) female fighters walk with their weapons in northern Deir al-Zor province ahead of an offensive against Islamic State militants, Syria February 21, 2017. (Photo by Rodi Said/Reuters)





Syrian Democratic Forces (SDF) gather in northern Deir al-Zor province ahead of an offensive against Islamic State militants, Syria February 21, 2017. (Photo by Rodi Said/Reuters)





Syrian Democratic Forces (SDF) stand on their military vehicle in northern Deir al-Zor province ahead of an offensive against Islamic State militants, Syria February 21, 2017. (Photo by Rodi Said/Reuters)





A Syrian Democratic Forces (SDF) female fighter adjusts a mortar in northern Deir al-Zor province ahead of an offensive against Islamic State militants, Syria February 21, 2017. (Photo by Rodi Said/Reuters)





A drone is pictured as a Syrian Democratic Forces (SDF) fighter gets into a military vehicle in northern Deir al-Zor province ahead of an offensive against Islamic State militants, Syria February 21, 2017. (Photo by Rodi Said/Reuters)





Syrian Democratic Forces (SDF) fighters gather as they have a meal in northern Deir al-Zor province ahead of an offensive against Islamic State militants, Syria February 21, 2017. (Photo by Rodi Said/Reuters)





A Syrian Democratic Forces (SDF) female fighter poses in northern Deir al-Zor province, Syria February 21, 2017. (Photo by Rodi Said/Reuters)





Syrian Democratic Forces (SDF) fighters cross a makeshift bridge in northern Deir al-Zor province, Syria February 21, 2017. (Photo by Rodi Said/Reuters)





A Syrian Democratic Forces (SDF) fighter sits near anti-tank missile in northern Deir al-Zor province ahead of an offensive against Islamic State militants, Syria February 21, 2017. (Photo by Rodi Said/Reuters)





A Syrian Democratic Forces (SDF) fighter poses in northern Deir al-Zor province, Syria February 21, 2017. (Photo by Rodi Said/Reuters)





A fighter from Jaish al-Islam (Islam Army) prepares a Russian-made sniper rifle in the rebel-held area of Harasta, on the northeastern outskirts of the capital Damascus, on February 21, 2017. (Photo by Amer Almohibany/AFP Photo)





A Syrian woman sits with injured children at a hospital following a reported strike by government forces in the rebel-held distric of Barzah, on the north-eastern outskirts of the capital Damascus, on February 20, 2017. (Photo by Saria Abu Zaid/AFP Photo)