The top U.S. military commander in Afghanistan wants to see intelligence from Kabul to support its claim that spies from neighboring countries encourage Afghan troops to turn on NATO forces.
U.S. General John Allen says Kabul has not yet shared such intelligence.
He said he wants to understand how Kabul came to this conclusion.
Allen said on August 23 that there are probably a variety of reasons for an increase of "insider attacks" by Afghan troops against NATO soldiers over the past year, including the infiltration of Afghan forces by the Taliban.
Kabul has been recruiting tens of thousands of police and soldiers to prepare for NATO's withdrawal by the end of 2014.
Afghan officials have admitted some insider attacks were carried out by recent recruits who were not properly vetted.
Based on reporting by AP and AFP