Clearly what agencies need is a situation where they can operate in safety inside Afghanistan

UNHCR spokesman Peter Kessler

The agency believes the most critical are some 700,000 people in and around the Panjshir Valley, the mountainous province of Badakhshan in the northeast of the country and the central highlands.

President Jacques Chirac of France has called for an international conference on aid, agreed by UN secretary Kofi Annan, to avert the "human catastrophe" in Afghanistan.

The conference would focus on logistical problems, Chirac said, which could be minimised through organisation and drive.

Taleban harassment

But UNHCR spokesman Peter Kessler said fundamental obstacles, including harassment by Taleban officials, would still stand in the way of aid operations.

"Clearly what agencies need is a situation where they can operate in safety inside Afghanistan," he said.

The UN says it is doing whatever it can

"Right now the problems with lawlessness, cooperation with the Taleban and the fact that many agencies have lost vehicles and offices to armed men are creating real problems on the ground.

"The World Food Programme (WFP) is getting in thousands of tonnes of aid by road. They are doing the best they can, but clearly much more needs to be done," he added.

The answer to this was their partnership with Afghan agencies, he said. Security is also a serious concern for them and communication is extremely difficult.

Neighbours criticised

Afghanistan's neighbours have also been criticised for not opening their borders to refugees desperate to find safety.

"Pressure must also remain on all the borders of countries surrounding Afghanistan to allow Afghans to seek asylum," Mr Kessler said.

"We are still seeing people turned away at border areas. Many Afghans who can't cross borders are stuck inside camps in remote areas.

People are still being turned away at borders

"Despite the tonnes of aid getting into the country we are still seeing children arrive in border camps malnourished and dying, in some cases before our eyes.

"This may only increase with difficulties faced in winter.

"Many Afghans don't even have the money or the energy to reach border areas but if the humanitarian situation worsens in the future they may try to trek out of the country," he added.

"This will certainly worsen their own condition and bring people into this border areas in an even more horrendous condition."

Winter preparations

The WFP has said it is buying 20 snow ploughs to keep mountain passes open for vital land access and is planning aid drops in three areas in Afghanistan.

But airdrops could cause further controversy among aid organisations who fear UN aid drops and US aid drops could cause utter confusion.

Aid agencies are desperate for access to the most needy

"This is one of the options that we are calling for in areas that are difficult to get to because of winter," said Oxfam's Matt Grainger.

"But it will be a real headache. The blur between humanitarian and military here could be a severe problem.

The situation is unique in that airdrops are dependent on approval from the US, which controls the air, and the Taleban on the ground, he added.

"The UN and other aid agencies must have 100% guarantees."

There is concern air-drop planes could be targeted as they carry out their deliveries.

Children immunised

Food entering Afghanistan is falling a long way short of the 52,000 tonnes of food per month the UN originally hoped for.

The UN has also begun a campaign to immunise Afghan children against polio, which is widespread in Afghanistan.

The three-day programme is principally focussed on border areas because of difficulties in working inside areas controlled by the Taleban.

The so-called National Immunisation Day is relying on cooperation from Taleban authorities to make it as effective as possible.