The United Nations last night warned that more than 20,000 civilians are in imminent danger of starving to death in a Palestinian refugee camp that has become a key battleground in the Syrian civil war.

The looming humanitarian crisis in Yarmouk, on the outskirts of the Syrian capital, Damascus, was described as “beyond desperate” by the UN Relief and Works Agency for Palestine refugees.

A fragile agreement between the warring factions to allow food into the camp has broken down, and for 10 days no food has been allowed through a government blockade of the area, the scene of fierce fighting between the Syrian Army and rebels.

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Chris Gunness, of UNRWA, said yesterday: “This is the 10th consecutive day that UNRWA has been unable to distribute food assistance. Given that a food parcel lasts for a maximum of 10 days, from tomorrow there will be no UN food in the camp.

“Even before this there were reports of deaths from starvation, mothers feeding their children with grass and spices picked up from the street. The situation in Yarmouk was already desperate. Now it is beyond desperate.”

Shape Created with Sketch. Satellite images show Syria devastation Show all 4 left Created with Sketch. right Created with Sketch. Shape Created with Sketch. Satellite images show Syria devastation 1/4 Syria This combination of two satellite images released by Human Rights Watch shows the Masha al-Arbíeen,neighborhood in Hama, Syria on 28 September 2012, top and on 3 October 2012 2/4 Syria This combination of two satellite images released by Human Rights Watch shows the Masha al-Arbíeen neighborhood in Hama, Syria on 28 September 2012, top and on 13 October 2012 3/4 Syria This combination of two satellite images released by Human Rights Watch shows Six-story residential building on fire likely from artillery shelling in the Tadamoun neighborhood of Damascus, Syria on 16 July 2012, top and 22 September 2012 and a six-story residential building demolished with controlled explosives, as visible on 22 September 2012 4/4 Syria This combination of two satellite images released by Human Rights Watch shows dozens of high-rise residential and commercial buildings along the main road between Mezzeh Air Base and Daraya, a Damascus, Syria suburb on 4 February 2013, top and on 1 July 2013 1/4 Syria This combination of two satellite images released by Human Rights Watch shows the Masha al-Arbíeen,neighborhood in Hama, Syria on 28 September 2012, top and on 3 October 2012 2/4 Syria This combination of two satellite images released by Human Rights Watch shows the Masha al-Arbíeen neighborhood in Hama, Syria on 28 September 2012, top and on 13 October 2012 3/4 Syria This combination of two satellite images released by Human Rights Watch shows Six-story residential building on fire likely from artillery shelling in the Tadamoun neighborhood of Damascus, Syria on 16 July 2012, top and 22 September 2012 and a six-story residential building demolished with controlled explosives, as visible on 22 September 2012 4/4 Syria This combination of two satellite images released by Human Rights Watch shows dozens of high-rise residential and commercial buildings along the main road between Mezzeh Air Base and Daraya, a Damascus, Syria suburb on 4 February 2013, top and on 1 July 2013

Until the outbreak of war in Syria, Yarmouk was a thriving haven for as many as 250,000 Palestinian refugees living alongside thousands of Syrians. But in December 2012 the area was infiltrated by rebel groups, who were branded “terrorists” by President Bashar al-Assad’s regime.

Civilians who could not escape found themselves trapped as a Syrian army bombardment reduced most buildings to rubble. In July 2013, government forces succeeded in imposing a tight blockade around the district. It wasn’t until January this year that a fragile agreement was brokered between all warring factions to allow in food.

Mr Gunness said even before the deal’s breakdown, the situation had been critical for some 18,000 Palestinians and more than 2,000 Syrian civilians trapped in Yarmouk. He said: “Only about 100 food parcels a day were getting through; 700 were needed.

“UNRWA is deeply concerned about the humanitarian crisis in a capital city of a UN member state, in the 21st century, as a result of direct political choice.”