The Saturday resolution does not threaten sanctions but it does express the council's intention to take "further steps" if the resolution is not implemented.

The foreign-backed militants hold several areas in the country under siege, leaving tens of thousands of people suffering from lack of food and medicine.

UN Secretary-General Ban Ki-moon welcomed the move, but said the 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," he said.

"Some 45,000 people are under siege in opposition-controlled areas."

Ban added: "If this resolution is implemented quickly and in good faith, at least some of the suffering can be eased."

Speaking at the UN, Syrian ambassador Bashar al-Jaafari said that the Syrian government had always welcomed efforts to improve the humanitarian situation in the country.

"Recently a number of conciliation processes have been carried out, sending a message to the world that Syrians can settle their differences among themselves." he said.

Syria has been gripped by deadly unrest since 2011. Over 130,000 people have reportedly been killed and millions displaced due to the unrest.

According to reports, the Western powers and their regional allies -- Qatar, Saudi Arabia and Turkey -- support the militants operating inside Syria.

NTJ/HH