NATO's military committee grouping chiefs of staff from all 28 alliance members said on Saturday that investing in Afghanistan's military was "key" to success there.
"We from the military point of view are convinced that investing in Afghanistan's national security forces is a key line of operation," committee president Admiral Giampaolo di Paola told journalists.
Di Paola, speaking after a committee meeting in Sintra near Lisbon, declined to comment on a report recently submitted by NATO's International Security Assistance Force (ISAF) commander in Afghanistan General Stanley McChrystal.
"We're in a process of assessing both politically and militarily the report that has been provided by General McChrystal," di Paola said.
This year more than 350 foreign troops have been killed in Afghanistan, making it the deadliest year since the invasion on October 7, 2001.
ISAF said on Saturday that a soldier -- whose nationality was not given -- was killed in a firefight in the south.
On Thursday six Italian troops and at least 10 Afghan civilians were killed in a suicide car bomb attack in Kabul.