More than 12 million Syrians need assistance because of increasing violence and deteriorating conditions in the country, up from 10.8 million in July, UN Humanitarian chief has said.
Half of the country's 22 million population have fled their homes with more than seven million displaced internaly and three millions crossing over to neighbouring countries.
"This is the largest number of people displaced from conflict in the world," Valerie Amos, the UN chief, said on Tuesday.
Speaking at the UN Security Council, Amos painted a grim picture of the situation with economy contracting by 40 percent since the start of the conflict, three quarters of the population living in poverty and a 50 percent drop in school attendance.
But Amos told the Council that the delivery of aid from Turkey and Jordan to rebel-held areas in the war-torn country without the government approval was making a difference. She urged the council to extend the authorisation for cross-border aid, which expires in January.
"I hope that this council will renew the provisions in resolution 2165," Amos said.
A UN report this month said that ten requests by the World Health Organization to deliver aid since October had gone unanswered by the Bashar al-Assad government.
Also on Tuesday, Syrian government air strikes on the ISIL-held city of Raqqa killed at least 90 people, activists have said.
About 125 more people were reported to have been injured in the air raids, which targeted a number of residential districts in the northern city. The majority of the dead and injured are believed to be civilians, including women and children.