The UN Security Council has authorised humanitarian access without Syrian government consent at four border crossings into rebel-held areas from Turkey, Iraq and Jordan, although Syria has warned it deems such deliveries an attack.

Monday's unanimously adopted resolution establishes for 180 days a monitoring mechanism for the loading of aid convoys in neighbouring countries, which will notify Syrian authorities of the "humanitarian nature of these relief consignments".

The shipments will travel through four different border crossings - two in Turkey (Bab a-Salam and Bab al-Hawa), one in Iraq (Al-Yarubiyah) and another in Jordan (Al-Ramtha).

All of these border crossings fall outside the control of the Syrian government.

"Aid access has to be authorised by the country receiving it," Al Jazeera's Kristen Saloomey, reporting from New York, said.

"This is a special measure by the UN, amid the growing humanitarian crisis," she said.

Because of the restrictions and ongoing insecurity, 10.8 million Syrians need help, of which 4.7 million live in hard-to-reach areas trapped by the fighting or under siege by government troops or rebels.

The United Nations accuses the Syrian regime of imposing bureaucratic and arbitrary obstacles to the delivery of humanitarian aid.

The Syrian government views aid entering the country without its approval as an "attack" on its sovereignty.

Two of the 15 Security Council members that approved the resolution were Damascus's allies Russia and China, which have in the past used their veto on four Syria-related resolutions since the conflict began in March 2011.

"These countries have always spoken about the need to keep Syria's sovereignty", Saloomey said. "But it seems that there is now an agreement that the humanitarian crisis has gotten out of control, and that the UN would know best how to address it."

Al Jazeera