( CNN) The United Nations Security Council will hold an emergency gratifying Wednesday on the dire humanitarian situation in the Syrian city of Aleppo, which a UN official described as a “descent into hell.”

French Foreign Minister Jean-Marc Ayrault called for the meeting on Tuesday. He told Reuters that Syria's brutal civil war, which has raged for almost six years, would not be resolved with one of the “biggest massacres on a civilian population since Word War Two.”