The Union Nations has condemned "barbaric" sieges in Syria and demanded immediate access to besieged towns to deliver aid to civilians. A divided Security Council has said all sides are culpable.
The Security Council met Friday to discuss thebesiegement of some 400,000 people in Syria.
The UN said half of the cities and towns are in areas controlled by the self-styled "Islamic State" (IS), whereas some 180,000 reside in government-controlled areas and about 12,000 in areas held by opposition armed groups.
"There can be no reason or rationale, no explanation or excuse, for preventing aid from reaching people," UN aid official Kyung-Wha Kang told an emergency Security Council meeting.
France and Britain requested the urgent talks after reports emerged of dozens of people who have died from starvation in the town of Madaya, where aid deliveries arrived only this week after months of blockade.
But Damascus' veto-wielding ally, Russia, accused Western powers of attempting to politicize a humanitarian crisis that risks derailing upcoming peace talks.
Russian Deputy Ambassador Vladimir Safronkov questioned the motives of Britain, France and the United States in calling for the meeting. He accused the nations of "double standards" by focusing on thesuffering in Madaya,
a rebel-held town besieged by Syria's government, while minimizing suffering in towns under siege by rebels.
"As the date for the launch draws closer there is all this unnecessary noise," Safronkov said, referring to the planned start of an inter-Syrian dialogue later this month.
Syria told diplomats in New York that no one cares more about the Syrian people than President Bashar al-Assad's government in Damascus.
"No one can claim to care more about our people than we do, no other country, especially when it comes to providing assistance to areas under the control of armed terrorist groups," Syrian deputy UN envoy Mounzer Mounzer told the 15-member council.
Friday's contentious debate was the second meeting the Council has held on the issue this week.
Dozens of aid trucks reached Madaya earlier thsi week where more than two dozen people are reported to have starved to death, after an outpouring of international concern and condemnation over the dire conditions in the town, where some 42,000 people are living under a government siege.
Aid agencies report dire situation
International relief organization Medecins Sans Frontieres (MSF) said it has confirmed 35 deaths from starvation in Madaya.
A mobile clinic with medics was dispatched to treat people suffering from malnutrition, the World Health Organization said, a day after a second aid convoy reached the town. UN officials said a teenage boy, 16-year-old Ali, became the latest victim of hunger, after he expired as medics were attempting to resuscitate him.
More than 260,000 people have died in Syria's conflict, which began in March 2011 with anti-government protests but has evolved into a complex civil war.
jar/sms (AFP, AP, dpa)