In a message released on Saturday, Shamkhani also expressed condolences to the Afghan people and government and sympathized with the families of the victims.
Suicide bombers struck two mosques in Afghanistan during Friday prayers, a Shia mosque in Kabul and a Sunni mosque in western Ghor province.
The attacks, claimed by the Daesh (ISIL or ISIS) terrorist group, killed at least 63 people at the end of a particularly deadly week for the troubled nation.