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Input: UNITED NATIONS (AP) — Secretary-General Antonio Guterres is again calling on the U.N. Security Council to refer Syria to the International Criminal Court  pointing to "serious violations" including blocking aid deliveries and medical care to millions.
 Guterres  said in a report to the council circulated Friday on the humanitarian situation in Syria in December that "accountability for serious violations is a requirement under international law and central to achieving sustainable peace."
During December   he  said  no aid was delivered to over 417 000 people in nine "besieged" locations  and only 60 000 of the nearly 2.5 million Syrians living in "hard-to-reach" areas received humanitarian help.  He  said 95 percent of the besieged population is besieged by Syrian government forces.
 Guterres  said "access for the United Nations and its partners to those people living in besieged and hard-to-reach locations remained a critical concern."
 He  said deliveries of food and other aid remained "extremely challenging" in many areas last month "as a result of active conflict  shifting conflict lines  administrative impediments and deliberate restrictions imposed on the movement of people and goods by the parties to the conflict."

UN chief calls for Syria referral to International Court