More than a hundred people, most of them children, died as a result of cold or illness in refugee camps in the Afghan capital alone last winter.

As winter approaches, more than half a million internally displaced persons (IDPs) in the war-ravaged country are facing death and hunger unless emergency assistance programmes are launched, warned the coalition comprising Amnesty International, the Norwegian Refugee Council and 28 other NGOs.

"We urge the government of Afghanistan, international donors and relevant humanitarian organisations to immediately launch a winter assistance campaign to help ensure adequate planning and preparedness to safeguard the lives of hundreds of thousands of IDPs across Afghanistan over the next few critical months," it said in an open letter to the UN, the Afghan government and international donors.

"What happened last year was a preventable tragedy, and should act as a sharp reminder that emergency assistance must be provided immediately before the winter arrives," said Polly Truscott of Amnesty International.

The organisations pointed out that refugee ministry's 2011 budget of $6 million was not enough to address the most basic needs and the international humanitarian appeal for Afghanistan had only been 34 percent funded.

"Afghanistan and the international community should remember that taking steps to safeguard lives in these camps is an obligation under international law", Truscott said.

Scarred by decades of war, social problems, poverty and insecurities, millions of Afghans still live as refuges mainly in neighbouring Iran and Pakistan. But with an ongoing Taliban-led insurgency plaguing the poverty-stricken country, Afghanistan's internally displaced population has reached half a million according to the UN refugee agency, though the actual number is likely to be much higher.