More than 2,100 civilians in Afghanistan were killed last year as a result of armed conflict, a 40 per cent rise from the previous year, the UN's humanitarian chief said Tuesday.

The estimate came in Geneva at the UN launch of a $604-million US funding appeal for Afghanistan for 2009 amid growing insecurity and concerns of a "worsening humanitarian situation" in the war-torn nation.

The UN's John Holmes cited the escalation of conflict spreading to new areas of the country as one of the reasons for the increase in civilian casualties, as well as the need for more international aid.

He did not specify whether the rising number of deaths was primarily due to Taliban insurgents or U.S. and NATO air strikes in the country, which have drawn condemnation from Afghan President Hamid Karzai.

"Coming on top of chronic vulnerability and widespread poverty, insecurity has contributed to the increase in acute humanitarian needs," Holmes said. "The lack of security in some areas also prevents humanitarian aid workers from carrying out their life-saving work."

Holmes listed severe food insecurity and the effect of the armed conflict on civilians as the "most pressing" problems. "Persistently high food prices, combined with recurrent drought, have compounded the humanitarian needs of a large part of the population," he said.

As a consequence of the drought, an estimated 1.2 million children under five and 550,000 pregnant and lactating women in 22 provinces are at high risk of malnutrition, he said.

From the funds, about $354 million will go toward food aid, while almost $100 million will be devoted to ridding the nation of landmines.

Holmes also noted that staff of UN aid agencies and non-governmental organizations have come under increasing attack in Afghanistan in recent years.

By the end of October 2008, 36 aid workers had been killed and a further 92 abducted, according to the UN Office for the Co-ordination of Humanitarian Affairs.