"We can confirm three International Security Assistance Force (ISAF) members died as a result of an enemy attack in Kabul today. Currently, Afghan officials and ISAF are reviewing the incident," the NATO-led ISAF said in the statement.
The attack took place around 8.10 a.m. when the bomber targeted an ISAF convoy in a four-lane street which leads to the Kabul international airport, Xinhua reported.
The statement gave neither the nationalities of the victims nor the details about the incident in keeping with the ISAF policy, adding it was ISAF policy to refer casualty identification procedures to the relevant national authorities.
13 Afghan civilians were also wounded in the attack
Furthermore, 13 Afghan civilians were also wounded and 17 civilian cars and several military vehicles were destroyed or damaged in the blast, according to the Afghan interior ministry.
Earlier reports said that three civilians and four NATO soldiers were killed in the attack.
The toll from Tuesday's attack has brought the number of foreign soldiers killed in Afghanistan to 63 this year.
More than 41,000 NATO-led ISAF troops, down from the peak of 130,000 in 2010, are stationed in Afghanistan. Nearly 29,000 of them are Americans and the US plans to trim its forces to less than 10,000 next year.
The blast occurred in the morning rush hour in a diplomatic district close to the US embassy, the Afghan Supreme Court and a foreign military camp.
Following the attack, the Taliban insurgent group claimed responsibility for the incident.