The UN Security Council has adopted a unanimous but non-binding resolution, calling for humanitarian aid convoys to be allowed access across war-torn Syria, but diplomats immediately voiced doubt about its effectiveness.

Syria's staunch ally Russia, with support from China, has blocked three previous resolutions aimed at pressuring the Damascus regime since the crisis began in March 2011, with an estimated half of all Syrians urgently awaiting immediate help.

But Moscow and Beijing, two of the five permanent Security Council members, did not do so this time, sending a strong message to President Bashar al-Assad, whose regime is accused of serious rights violations in attempting to hold on to power.

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

The regime and opposition forces 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.

"Profoundly shocking to me is that both sides are besieging civilians as a tactic of war.

"Some 200,000 people are under siege in regime-controlled areas - and 45,000 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 Jaafari said that the Syrian regime 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.

Wave of aerial bombardment

The resolution comes on a day Syria's air force staged more air raids on the key opposition-held bastion of Yabrud north of Damascus, as clashes also raged on the capital's outskirts, a monitoring group told AFP news agency.

The Syrian Observatory for Human Rights also said that in the northeast, Kurdish fighters seized the town of Tal Barak from jihadists.

Regime forces launched a new wave of aerial and tank bombardment in and around Yabrud, the main town in the Qalamun mountain range and with a mixed Muslim and Christian population, two weeks into a campaign aimed at seizing it from opposition forces.

Also on Saturday, Syrian regime forces captured two opposition-held areas on the edge of the Israeli-occupied Golan Heights after days of intense fighting near a decades-old cease-fire line between Syria and Israel, AP said quoting state TV.

The Syrian TV report, citing a military official, said troops and pro-regime gunmen known as National Defense Forces captured the areas of Rasm al-Hour and Rasm al-Sad, south of the town of Quneitra.

PHOTO CAPTION

Syrian Ambassador to the United Nations, Bashar Ja'afari (R) speaks after the UN Security Council voted on a resolution to boost humanitarian aid access in Syria, at United Nations headquarters in New York, New York, USA, 22 February 2014.

Aljazeera