GENEVA -- The United Nations said that the humanitarian crisis in Syria has reached "catastrophic" proportions, with some 2.5 million people in the war-ravaged country lacking enough food.

Jens Laerke, a spokesman for the UN Office for the Coordination of Humanitarian Affairs, said that continued fighting could push up the numbers of those affected by the fighting. He said some 4 million people are in need of urgent assistance now while over 2 million people are displaced inside Syria. Those numbers will go up significantly if the fighting continues, he said.

Despite the world body enlisting the help of more than 70 local groups in Syria and delivering more aid to opposition-controlled areas, Laerke said that "the catastrophic humanitarian crisis continues to deepen."

The UN World Food Program, meanwhile, said that 2.5 million people inside Syria lack enough food. A spokeswoman for that agency, Elisabeth Byrs, said they plan to feed 1.75 million this month, then up to 2 million in March and reach 2.5 million in April.

Speaking to reporters from Damascus, Elizabeth Hoff, the UN World Health Organization's representative for Syria, told of seeing out her window "black smoke from every corner of the city" and difficulties in reaching rural areas of the capital.

"When we talk about 4 million people who are critically in need, this number is growing every day," she said. "Areas around rural Damascus cannot be reached which we reached a week ago."

Hoff said the country's health minister told her the national hospital in the central province of Homs was destroyed over the last few days, and some 78 per cent of the country's ambulances are damaged.

More than half of Syria's ambulances do not work, she added, and many others are out of circulation because they are being used by Syria's military and armed opposition.

The UN says that over 60,000 people have died in Syria since the conflict began in March 2011. The armed opposition to Syria's President Bashar Assad remains outgunned by government forces despite significant rebel advances on the battlefield.