BEIRUT, Jan 18 (Reuters) - A food aid delivery reached a besieged suburb of Damascus on Saturday, resident activists said, badly needed after months of isolation but not enough for thousands of trapped civilian who are malnourished and without medicine.

The delivery was the first to the Yarmouk Palestinian district, where 15 people have died of malnutrition and 18,000 are trapped, since forces loyal to President Bashir al-Assad imposed the siege seven months ago.

An attempted United Nations aid trip on Monday was aborted when gunfire erupted but a safer route was used on Saturday, residents said.

An activist in Yarmouk, who asked to remain anonymous as the topic is sensitive, said that only 50 food parcels had arrived. "The supplies entered from a government-held checkpoint. Women are gathering to take the supplies," he said.

Aid workers in Syria have accused authorities of hampering deliveries to opposition-controlled areas and threatening groups with expulsion if they try to avoid bureaucratic obstacles to help those trapped in an almost three-year civil war.

Syria blames rebel attacks for aid delays.

The Yarmouk activist said the food distribution was organised by local Palestinian groups in Yarmouk. State media said a delivery was made but did not give details.

Syria is home to half a million Palestinians, refugees of the 1948 conflict which led to the creation of the state of Israel. Before the 2011 uprising against Assad, many lived in Yarmouk on the southern edge of the Syrian capital.

Since then, around 70,000 Yarmouk residents have fled.

Those that remain have been trapped with rebels under the government siege. Opposition activists say residents have survived by scavenging for food and highly dangerous smuggling trips. The United Nations has called for greater access.

Chris Gunness, spokesman for the U.N. Relief and Works Agency (UNRWA), said it donated 200 food parcels on Saturday after authorities requested its support for the delivery.

"In this instance, UNRWA is playing only a support role. Today's effort is not an UNRWA convoy and UNRWA is not involved or engaged in the transport of the food parcels into Yarmouk or its distribution inside Yarmouk," he said in an email.

It is not clear if all the 200 parcels had made it in. They would not be enough to feed all the trapped civilians.

Shooting forced the United Nations to abort a delivery on Monday of food and polio vaccines to Yarmouk after the Syrian government said it should use a circuitous and dangerous route, UNRWA's Gunness said on Wednesday. (Reporting by Oliver Holmes and Reuters TV)

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