IS "as an external threat is significant and of concern, but it is not widespread across the (Afghan) nation. They have not been able to gain momentum in Afghanistan," Maj. Gen. Gordon Davis, Commander of Combined Security Transition Command-Afghanistan, told reporters here.
He noted that the Taliban, the Afghan army and police with local tribes are all fighting IS so, they were more retreating than they are gaining.
He said the majority of IS fighters in Afghanistan were "disenfranchised Taliban," and some foreign fighters.
Davis was also responsible in NATO's Resolute Support Mission to oversee the financial support to the Afghan national army. He was in Brussels to participate in the meeting of the Afghan National Army Trust Fund Board held on Wednesday.
At the meeting, NATO Allies and its partners together with its representatives of the donors' community reaffirmed their commitment to continue support the financial sustenance of the Afghan security forces.
The Afghan nation army requires $5 billion per year to sustain their current force level at 195,000 for the army and 157,000 for the police up till the year 2020.
NATO and allied nations have confirmed funding pledges for around $450 million per year throughout 2015 and into the end of 2017.