Kunar has seen some of the fiercest fighting of the conflict
US and Afghan troops have abandoned a remote village in eastern Afghanistan where militants killed nine US soldiers and wounded a dozen more on Sunday.
A statement said the outpost had been temporary and that "regular patrols" in the area would be maintained.
Afghan police are continuing to fight insurgents after the pullout on Tuesday, local officials say.
The attack caused the biggest American loss of life in battle in Afghanistan since operations began in 2001.
Nato says the rebels also suffered heavy casualties.
It did not name the attackers but there has been a sharp increase in Taleban attacks in the country, and in that region in particular, although other rebel groups are also known to operate there.
At least 100 - some reports say 200 - insurgents stormed the small combat outpost in the village of Wanat on the border of Nuristan and Kunar provinces on Sunday.
Some militants briefly broke through defences and into the temporary base.
"We are confirming that we have vacated our combat outpost at Wanat," said Nato spokesman Mark Laity.
The outpost had only been constructed days before it was attacked.
Nato's International Security Assistance Force (Isaf) announced the camp had now been "disestablished" but said there would be a "continued presence" in the area - namely patrols and the use of Afghan security forces.
Omar Sami Taza, a spokesman for the governor of Nuristan, said US troops had withdrawn from the area, "leaving the district in the hands of only 20 policemen".
"American troops have taken all heavy weapons out of the district," he told the BBC. "This is why we have lost the district to the Taleban because our police couldn't defend it with one AK-47."
However, the local police chief, Hazarat Ali, told the BBC: "Our police are still in the district, the elders are backing us. We have not lost our district."
The BBC's Alastair Leithead in Kabul says there are many of these small outposts scattered across eastern Afghanistan as part of the US counter-insurgency strategy which is being followed to the letter in this area.
Our correspondent says the idea is to get small groups of international troops and Afghan security forces out on the ground as a permanent presence to instil more confidence in the local people and show they can provide security, rather than just visiting the area on patrol.
The danger for Nato is they risk being outnumbered and attacked, or even overrun, as almost happened in the raid at the weekend.
There had been reports from Afghan local officials of civilian casualties caused by bombing in the aftermath of the attack on the base, but Nato also put out a statement denying this.
They said the only bombs dropped were more than 40km (25 miles) away from the villages named by local officials.