The resolution passed on Saturday was drafted by Australia, Jordan and Luxembourg and had the backing of Britain, France and the United States. It threatens "further steps" in the case of non-compliance.
The resolution "demands that all parties, in particular the Syrian authorities, promptly allow rapid, safe and unhindered humanitarian access for UN humanitarian agencies and their implementing partners, including across conflict lines and across borders."
It also "demands that all parties immediately cease all attacks against civilians, as well as the indiscriminate employment of weapons in populated areas, including shelling and aerial bombardment, such as the use of barrel bombs, and methods of warfare which are of a nature to cause superfluous injury or unnecessary suffering."
Russia and China voted in favor of the resolution. The two permanent Security Council members have blocked three previous resolutions condemning Syria and threatening the country with sanctions.
Secretary General Ban Ki-moon told the Council: "This resolution should not have been necessary. Humanitarian assistance is not something to be negotiated; it is something to be allowed by virtue of international law."
"Profoundly shocking to me is that both sides are besieging civilians as a tactic of war," Ban said after the vote.
The resolution asks Ban to report back to the council in 30 days on the implementation of the resolution and "expresses its intent to take further steps in the case of non-compliance."
UN aid chief Valerie Amos said in a statement after the vote in the Council: "I hope that the passing, by the United Nations Security Council, of a humanitarian resolution will facilitate the delivery of aid to people in desperate need in Syria."
The UN says 9.3 million people need help and that well over 100,000 people have been killed in the civil war in Syria.
jm/rc (Reuters, AP, AFP)