UN - The UN humanitarian chief accused the Syrian government on Thursday of blocking aid to hundreds of thousands of the country's neediest people despite a nationwide cease-fire that has given "a glimmer of hope" that the conflict might be coming to an end.Undersecretary-General Stephen O'Brien told the Security Council that a two-step approval process that the government agreed to for humanitarian convoys to cross conflict lines to get to besieged and hard to reach areas "has become, in practice, a 10-step process."Minimal accessDespite the December 30 cease-fire and a humanitarian task force whose sole purpose is to ensure access, he said, "we continue to be blocked at every turn, by lack of approvals at central and local levels, disagreements on access routes, and violation of agreed procedures at checkpoints by parties to the conflict."O'Brien said the result is that only one convoy delivered aid to 6 000 people in December, when the UN asked for approval to help 930 250 people - and he criticised the removal of over 23 000 medical items from the trucks that did get through. So far in January, he said, the situation isn't much better with just a single convoy reaching 40 000 people.O'Brien said the Syrian government did respond to the UN's monthly convoy plans within the agreed seven working days."But subsequent administrative delays on the part of the government, including in the approval of facilitation letters, approval by local governors and security committees, as well as broader restrictions by all parties continue to hamper our efforts," he said.A call to Syria's UN Mission seeking comment was not answered.‘Staggering’ humanitarian needsO'Brien urged council members with influence to pressure the Syrian government to allow aid deliveries to all besieged and hard to reach areas.The council, in a statement, urged all parties "to intensify efforts to ensure sustained and unhindered humanitarian access."As a result of the evacuation of rebel-held eastern Aleppo and a comprehensive UN review, O'Brien said the number of besieged areas has been reduced from 16 to 13, and the number of people estimated to be living in those areas has dropped from some 974 080 to some 643 780.He singled out four areas where humanitarian action "remains greatly needed and, sadly, often contested."Humanitarian needs in Aleppo "continue to be staggering," O'Brien said, with at least 160 000 people temporarily displaced. In eastern Aleppo, he said over 65 000 people have been registered as having returned or stayed, most living in damaged houses.Searching for an endHe added that the UN is following up on reports that "stockpiles of humanitarian supplies" have been found in east Aleppo since late December when government forces and their allies took control.O'Brien also expressed concern for the safety of 93 500 people in the besieged western side of Deir el-Zour following reports of attacks by fighters from the Islamic State extremist group, and for over 400 000 people in need of aid in Raqqa, the Islamic State group's headquarters.The UN is also deeply troubled at the cut-off of the main water supply to some 5.5 million people in Damascus, and O'Brien said if this was deliberate "those responsible may have committed a war crime."O'Brien warned that the humanitarian crisis won't end until the conflict, now in its sixth year, ends and he urged the council to rally behind UN-led negotiations to find a political solution. The Security Council also called for stepped-up efforts to consolidate the cease-fire and reiterated support for a political solution.