Militants wearing Afghan army uniforms attacked a remote NATO base Wednesday in mountainous Nuristan province, killing two Afghan soldiers and wounding 11 NATO troops.
"After the attack of yesterday, we'll send more detailed guidance in order to control this in accordance with the government of Afghanistan," said Maj. Gen. Giorgio Battisti, deputy commander in charge of logistics for the NATO force there.
Speaking from Kabul by video link to reporters at NATO headquarters in Brussels, he said Afghan army uniforms were easily available for sale outside the country.
"It is a matter for the government of Afghanistan to check this but as I said, it's probably coming from outside Afghanistan," he said.
Violence in Afghanistan is currently running at its highest level since U.S.-led forces invaded in 2001 - particularly in the south and east - but Battisti said the NATO force of 40,000 was making progress in stabilizing the country.
"More than 60 percent of Afghanistan is calm and stable," he said.
Battisti said the insurgents had presented little threat to communications lines bringing in fuel and other supplies to NATO troops from Pakistan. He said snowfall, flooding and the poor condition of Afghanistan's roads were a greater problem.