"At this time, we can confirm there are no USA or NATO Resolute Support fatalities", the mission said in a statement.
On June 11, three US soldiers were killed and one was wounded in an insider attack at a base in Nangarhar Province in eastern Afghanistan.
The shootout at Camp Shaheen near northern Mazar-i-Sharif city is the second "green-on-blue" attack - where Afghan soldiers turn their weapons on worldwide forces assisting them - reported this week. Two others were shot dead by police, while one was still fighting.
Al Jazeera's Rob McBride, reporting from Afghanistan's capital, Kabul, said North Atlantic Treaty Organisation soldiers were training their Afghan counterparts at the base where the attack took place.
Meanwhile, the Pakistan embassy in Kabul said in a statement on Monday that Pakistan too intends to open a transit route for Afghan exports. In March another insider attack killed three USA soldiers.More news: Carrick not thinking about Ronaldo reunion at Man Utd
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Abdul Qahar Araam, spokesman for the Afghan army's 209th Corps, had announced that an Afghan soldier shot and killed four USA troops inside the base.
ISIS claimed responsibility for a deadly attack on a mosque in Kabul on Thursday.
According to Tolo News, the attacker was killed by his colleagues following the shooting.
He said that an investigation was ongoing into the circumstances of the attack.
The Pentagon is weighing the possibility of sending thousands more troops to the country to train Afghan forces to break what Lt. Gen. John Nicholson calls a stalemate there.
The Pentagon is set to announce it is sending another 4,000 USA troops to the country to counter the increasingly aggressive insurgents.
American defense officials say in coming weeks they will decide whether to send between 3,000 to 5,000 more troops as requested by military commanders. He had initially announced that three USA soldiers had been wounded. "We hope to extend air cargo flights to other cities between India and Afghanistan", said Gopal Bagley, spokesperson of Ministry of External Affairs.