"It's been approved," a Nato official in Brussels said on Friday.
The official said it would include an engineering battalion, plus additional staff, and a small number of helicopters.
Jan Egeland, the United Nations' top aid official, incensed by what he saw as a woefully inadequate response to the most difficult relief operation the world has ever seen, had called on the military alliance to launch a huge operation to get survivors to safety.
Helicopters are the only means of getting quickly deep into the Himalayan foothills of Pakistani-administered Kashmir and North West Frontier Province where 51,000 people are known to have died.
That toll, in addition to 1300 who were killed on the Indian-administered side of Kashmir, is expected to climb much further as thousands now face a freezing winter without shelter.
Pakistan said the number of injured, now 74,000, could also leap because large areas that were hit by the earthquake have not yet been reached.
After Egeland made his appeal directly to Nato ambassadors in Brussels on Friday, the alliance agreed to study sending up to 1000 soldiers, including an engineering battalion, a Nato official said.
But there would be only a few helicopters. "Not a large number - less than five," the official said.
Egeland appealed directly to
Nato ambassadors in Brussels
Nato spokesman James Appathurai said that while aid work was not the alliance's "bread and butter", it had already transported more than 1000 tons of supplies to Pakistan's earthquake victims and 40% of the helicopters flying there were from Nato nations.
"We are very much focused ... on what more we can do," Appathurai told CNN television.
The closest source of helicopters would be India, but it has fought two wars with Pakistan over Kashmir.
Pakistani President Pervez Musharraf told India he would accept helicopters, but only if they came without crews given the enormous political sensitivity.
India said no, and Egeland called on the two governments to figure out a compromise fast. "These discussions are now holding up a bigger operation and they shouldn't. I would want them to work out a compromise immediately," he said.
"These discussions are now holding up a bigger operation and they shouldn't"
Chief Emergency Relief Coordinator, UN
Egeland and other aid officials with experience of both said the earthquake relief operation was more difficult than that in the wake of last year's Indian Ocean tsunami, which killed more people but hit coastlines that ships could reach easily.
The United Nations has received $57 million in firm, legally binding commitments and $33 million in promised pledges for a total of $90 million towards its $312 million appeal for Pakistan, spokeswoman Elisabeth Byrs said in Geneva.