The UN Security Council unanimously approved a resolution Monday authorizing cross-border delivery of humanitarian aid to Syrians in rebel-held areas in desperate need of food and medicine, without government approval.

The resolution, an unusual agreement on Syria among the often divided council, expresses "grave alarm at the significant and rapid deterioration of the humanitarian situation in Syria" and deplores the fact that its previous demands for humanitarian access "have not been heeded" by the government and opposition fighters.

The council has been deeply divided over Syria, between Russia and China, key allies of Syrian President Bashar Assad, and the United States and its European allies, who have backed the opposition.

It has never been able to adopt a legally binding resolution calling for an end to the conflict, now in its fourth year with over 150,000 people killed.

In February, the council reached a rare agreement and adopted a resolution focusing on the growing humanitarian crisis and demanding that all sides in the conflict allow immediate access for aid, lift the sieges of populated areas, stop depriving civilians of food, halt attacks against civilians and withdraw foreign fighters. It expressed the council's intention to take "further steps" if its demands were not fulfilled.

Monthly reports to the council since then by UN Secretary-General Ban Ki-moon on the resolution's implementation have described an increasingly dire situation.

UN humanitarian chief Valerie Amos told the council on June 26 that the number of Syrians in need of humanitarian assistance has increased from one million in 2011 to 10.8 million, a surge of 1.5 million in just the last six months. That includes 4.7 million in hard-to-reach areas, and over 240,000 trapped in besieged areas.

All through Damascus

All humanitarian aid must now go through Damascus and the vast majority goes to government-controlled areas.

The resolution adopted Monday focuses primarily on getting aid, which most now go through the Syrian capital Damascus, to those hard-to-reach areas under rebel control.

It authorizes UN agencies and aid organizations that assist them to use routes across conflict lines and four border crossings — two in Turkey, one in Iraq and one in Jordan — in addition to those already in use to ensure the delivery of humanitarian assistance. It allows the United Nations to monitor the loading of all aid shipments in the three countries before they cross the Syrian border.

The resolution requires Syrian authorities to be notified of shipments "to confirm the humanitarian nature of these relief consignments" — but the government would not control the delivery of aid as it now does.