"One of the key reasons why we have started this process is because of Monday's terrorist attacks. It is possible that the attackers use fake IDs. The key decision for me is the security of the people and we must know who are Afghans," TOLO News quoted Ghani as saying at a ceremony at which he received the first card to be issued.
The move faced immediate opposition in his own government, according to the reports.
Some members of other groups, notably Persian-speaking ethnic Tajiks, have objected to the usage of the term, saying that such a move would make the identity of the Pashtuns equivalent to that of the nation as a whole.
They form the largest ethnic group in Afghanistan.