The top U.N. relief official has renewed his urgent appeal for Pakistan earthquake aid, pointing to forecasts of an unusually harsh winter in the region. Relief workers are facing a severe test as temperatures plummet in the higher elevations of the rugged Kashmiri mountains.

A month after an earthquake killed some 73,000 people and left three million homeless, the race to keep hundreds of thousands more from freezing to death is moving at an agonizingly slow pace.

Top U.N. relief coordinator Jan Egeland describes a grim scene, with weather forecasters predicting a colder than normal winter, and donors with little left to give after a year of unprecedented natural disasters. He says the earthquake relief effort presents an unusually difficult challenge.

"We have a severely overstretched humanitarian system, and we have donors with empty pockets because it's the end of their budget year. People freeze to death if they don't get assistance within weeks. It's even more urgent than it was in these other hurricanes, and tsunamis and situations like in Africa because it's now freezing temperature in addition to all the other problems," he said.

Mr. Egeland says weather forecasters are predicting heavier than normal snowfalls beginning soon in the quake-hit region, and continuing for months. "It's predicted that around the epicenter, there will be one foot of snow this month, five feet in December, eight feet in January. So this is the whole nature of this race against clock that we've been talking about for some time, we've got weeks more before the whole area covered by deep snow," he said.

Mr. Egeland says overall, donors have pledged more than one billion dollars in aid for earthquake victims. Only a little more than 10 percent of that total is being channeled through the United Nations. "We have $133 million pledged or contributed to our appeal. Outside of the appeal, which could be through the U.S. military or NATO or Red Cross or whoever is outside the appeal, there is $232 million. All together, it's $1 billion, in excess of $1 billion that has been pledged," he said.

He says the bulk of the remainder of the aid is coming in the form of general bilateral assistance, much of it from Gulf States and other countries in the region.

Mr. Egeland says U.N. relief workers are desperately trying to reach the estimated 200,000 people in heavily-damaged mountain villages above the snow line. They are also planning to care for 350,000 people expected to be coming down from the mountains and into camps for the winter.

The plan is to provide 10,000 extended rural families with one warm room to gather in before it gets too cold.