Iran's Guardians Council has adopted a legal amendment allowing Iranian women married to foreigners to pass on their nationality to their offspring.
Abbas Ali Kadkhodaei, spokesman for the constitutional body, announced the move on October 2, more than four months the measure was approved by parliament.
The Guardians Council, which vets legislation passed by lawmakers for compliance with the constitution, had rejected two previous texts of the bill.
Human rights activists have long called for the reform of Iran’s "discriminatory" citizenship law, saying it could help thousands of children living in legal limbo in the country.
The amendment allows Iranian women married to men with foreign nationality to request Iranian citizenship for their children.
It still requires the Intelligence Ministry and the Intelligence Organization of the Islamic Revolutionary Guards Corps (IRGC) to certify that there is no "security concern" before Iranian citizenship can be granted.
After the reform was approved by parliament in May, Human Rights Watch (HRW) said that allowing Iranian women to pass on their nationality to their children could improve access for these children to health care, university education, and work.
It is unclear how many children in Iran have Iranian mothers and foreign fathers, according to the New York-based human rights watchdog, but the issue has come to prominence in recent years due to a large number of marriages between Iranian women and Afghan migrant men.
There are an estimated 3 million Afghans currently living in Iran.