The UN's top relief official in Pakistan has welcomed Nato's offer of troops and helicopters to help with quake relief but says more is needed.
Aid agencies say there is a potential shortage of 200,000 tents
"The immensity of the disaster is still becoming clearer daily," Jan Vandermoortele told a press conference.
Aid agencies are worried that many more people could die as a result of cold weather and say they need more tents, emergency shelter and helicopters.
More than 50,000 people have been killed and up to 3m are homeless.
Jan Vandermoortele said: "Progress is being made. However people in the valleys remain unreached, the terrain is making it a logistical nightmare to sustain the support."
"The scarcest commodity at this time is time. The weather is against us, winter is closing in. We have to quicken the pace and we have to scale up the action on the ground," he said.
Shortage of tents
Meanwhile, Chris Lom of the International Office of Migration said there was a shortfall of up to 200,000 tents, required to house those displaced by the earthquake.
Nato announced on Friday that it would deploy between 500 and 1000 troop to help with the relief effort, including a battalion of engineers, some medics and a small number of helicopters.
But in an interview with the BBC on Friday Pakistani President Pervez Musharraf described the amount of aid pledged so far as "totally inadequate".
He said that about $620m had been promised but that Pakistan needed about $5bn to rebuild devastated areas.
Speaking during a visit to Finland, World Bank President Paul Wolfowitz also said the Pakistan would need billions of dollars of assistance.
"The scale of the disaster is so enormous that frankly, right now, a big part of the effort has to go to figuring out what the needs really are," he said.
"But they're going to need a lot of help, probably to the tune of several billion dollars."