The Taliban claimed responsibility for the attack.
Bagram Airfield, America´s largest air base in Afghanistan, is located about 50 kilometres (30 miles) north of Kabul. The Defense Department said it was withholding the names of the fallen Americans until 24 hours after their families had been notified, per normal Pentagon policy. "The contractor, an Afghan citizen, was initially treated along with other injured civilians, later identified as a contractor and treated at Bagram Airfield".
In addition, three US service members were wounded in the blast. On Twitter, a spokesman for the militant group said that a suicide bomber targeted "a convoy of American occupiers" near the base's gates.
Authorities in Afghanistan say the latest military-led offensives, backed by coalition airpower, have killed almost 100 Taliban insurgents and injured dozens more in a bid to reclaim full control of a volatile district in western Badghis province.
On Tuesday, local Afghan officials said at least five Afghan civilians were wounded in the commotion after the attack on the American convoy.
The attack brings to seven the number of American troops who have been killed this year in Afghanistan.
The Council reaffirmed its political commitment and long-term support to the people of Afghanistan on their path towards peace, security and prosperity and asked all parties in the conflict, including the Afghan government the Taliban and to engage in intra-Afghan talks as soon as possible.
The Taliban has until now refused to meet with the Kabul government, accusing it of being a puppet regime.
"US service members have sacrificed their lives in Afghanistan to keep us safe and no cowardly act of terror will impede our efforts to achieve peace", he said. But the Taliban say they will not recognize any government official attending the gathering as a representative of the Kabul government, only as an individual Afghan participant.