Afghan Interior Ministry Spokesman Yousuf Stanizai says two suicide bombers in a station wagon attacked Sibghatullah Mujaddedi's convoy on a busy Kabul road.
"This morning at 9:30 Mr. Mujaddedi was targeted by two suicide attackers. Fortunately Mujaddedi is safe and unharmed, but two other civilians were killed in the attack, three others were injured," Stanizai says.
Stanizai said no one had claimed responsibility for the attack.
Former president Mujaddedi currently chairs the upper house of the new parliament and heads a commission working to encourage Taleban insurgents to surrender.
Speaking to reporters, Mujaddedi accused the Pakistani security agency, the I.S.I., of orchestrating the assassination attempt.
The I.S.I. has a history of involvement with the Taleban movement. But the agency publicly disowned the hard-line Islamic group after the September 11th 2001 terrorist attacks in New York and subsequent U.S.-led counterterrorism operations, which resulted in the overthrow of the Taleban government in Afghanistan.
Pakistani officials vehemently denied Mujaddedi's allegations.
Two weeks ago Mujaddedi told reporters he suspected the Taleban would try to kill him because he has been so successful at winning over militants from the Islamic group.
The insurgency in Afghanistan has gathered force lately, with at least two-dozen suicide attacks in the past five months.
Explosions aimed at foreign troops and thr government have rocked the capital Kabul, which had been relatively stable.
Interior Ministry Spokesman Stanizai says the government is stepping up its counterinsurgency efforts, but suicide attacks will likely continue.
"Taleban and al-Qaida are always trying to disrupt the security situation in the center and as well as the provinces. There is no way to prevent suicide attacks," Stanizai says.
Afghan officials allege many of the attacks are planned across the border in Pakistan, where, they say, insurgents have established training camps.