NEW YORK

Outgoing UN aid chief Valerie Amos painted a brutal portrait of Syria's civil war on Thursday in her final briefing to the Security Council.

"For more than four years, we have watched Syria descend into deeper depths of despair, surpassing what even the most pessimistic observers thought possible," she said. "The situation throughout the country is, by any measure, extremely grave and deteriorating by the day."

The UN says more than 220,000 people have been killed in Syria since the onset of the violence in March 2011, but the number is likely much higher.

Some 12.2 million people need humanitarian assistance throughout the country, as well as more than 4.8 million trapped in hard-to-reach areas, according to the UN.

"In the past weeks, we have seen more and more heinous acts. Innocent men, women and children killed, maimed, displaced, and subjected to a savagery that no human should have to endure," Amos said.

She particularly cited an aerial bombing of a market in Darkoush in rural Idlib in northeastern Syria at the end of April, in which up to 50 people were killed and over 100 civilians wounded.

The same market was reportedly targeted once again last week with reports of 20 more people killed.

“People are trying to survive by the day, without the basic necessities of life such as water and electricity,” Amos said. “And parties to the conflict continue to cut services, collectively punishing entire villages and cities in the process.”

The UN’s top humanitarian official, who will hand over the post to fellow British politician Stephen O'Brien, also urged the Security Council to set aside political differences and find a solution to Syria’s “intractable” problems.

“The international community more broadly needs to do more to protect civilians and ensure greater accountability for violations of international humanitarian law," she added.