At least six NATO soldiers were killed and another six were wounded in separate incidents in Afghanistan on Sunday
Four Norwegian soldiers died Sunday when their vehicle was hit by a roadside bomb in the northern province of Faryab.
Two other NATO soldiers were killed and another six were wounded in a joint operation conducted by Afghan and coalition forces in the eastern Kunar province.
An Afghan soldier was killed and another three were also wounded in these operations.
ISAF media report said the operation was conducted to wipeout Taliban militants from two villages of Marora district in Kunar province.
The exact number of Taliban casualties in these operations has not been confirmed.
Taliban claim that ten foreign soldiers were killed and one Taliban fighter was wounded in these attacks.
A total of 315 NATO soldiers have been killed in Afghan conflicts so far this year, according to icasualties.org, an independent US website that tracks military casualties in Afghanistan and Iraq.
Meanwhile, in Washington the head of the CIA, Leon Panetta, acknowledged there were "serious problems" with the prosecution of the war in Afghanistan.
"We're dealing with a country that has problems with governance, problems with corruption, problems with narcotics trafficking, problems with a Taliban insurgency," Panetta told ABC's "This Week."