"There is an urgent need to diversify distribution of food supplies in remote areas of northwest Afghanistan," said the World Food Program.
The report said that even in areas where relief has arrived, "supplementary foods such as lentils, oil and corn Soya blend are needed to meet the nutritional requirements of malnourished populations."
WFP began distributing food coupons to over 50,000 families (approximately 340,000 people out of a total population of 430,000) in the western Herat region this week. More than 2,600 metric tons of wheat will be distributed over the next 10 days.
But the International Rescue Committee, one of the aid agencies working in Afghanistan, warned that about 10,000 people in the northern mountainous region of Abdullah Jan have been forced to eat grass.
WFP is also taking food to another 10,000 starving people in Badhgis district of western Afghanistan who face a similar situation.
The Red Cross estimates that 300,000 to 400,000 families could still be in remote mountain areas and in desperate straits.
"It's true, there's real crisis there," Ken Burslem, a spokesman for the International Rescue Committee told British Broadcasting Corp.
Logistical problems are also preventing aid agencies and U.N. officials from reaching the affected area. Years of war and the chaotic Taliban rule have destroyed whatever infrastructure Afghanistan had. Most of the remote areas have no road, no transport and no distribution network.
A recent supply of 1,000 tons of flour from WFP took two weeks by truck, and four and one-half hours by donkey to reach famine-hit areas of northern Afghanistan.
Although U.S. forces have dropped hundreds of food packages in remote areas, aid agencies say this did not help much. According to the agencies, most of the food packages were collected by warlords and sold in the local market or fell in areas infested with land mines.