Iran ends state-backed contraception and vasectomies in bid to boost population
With marriage down by 40 percent in 10 years, matched with a decline in children within marriage, the country's annual population growth has dropped below 1 percent.
If no action is taken, around a third of the country will be over the age of 60 by 2050, making it one of the world's oldest countries.
"Whether we like it or not … we will become an ageing country," Hamed Barakati told IRNA in an interview.
Barakati added that contraception would be available for women at risk of life-threatening complications from pregnancy.
Private hospitals would also still provide family planning procedures, he added.
Iran's Supreme Leader Ayatollah Ali Khamenei and fellow hardliners in the government, have long been pushing for citizens to have more children.
The latest move follows a string of pro-birth rate refores, including limiting access to family planning services, increasing the number of infertility clinics and extending maternity and paternity leave.
Barakati acknowledged that the persistent fall in marriage and birth rates is due to economic hardship.
"The young man will not be willing to marry or have children, even if we give him a loan, as long has he does not feel secure," he said.
Barakati added that the government also needed to address the fact that women delay marriage and children in favour of higher education, as well as a societal norms of not having more than two children.
The latest policies, which were first discussed in 2015, have been slammed by human rights groups as "misguided" and a danger to women.
Amnesty International said in 2015 that Iranian authorities "are promoting a dangerous culture in which women are stripped of key rights and viewed as baby-making machines rather than human beings with fundamental rights to make choices about their own bodies and lives".
Iran implemented a successful population control policy following a population boom after the 1979 revolution, which saw the average number of children per family reduce from seven to two.
However in recent years, Khamenei has blamed the declining birth rate on imported western norms, and called for the population to almost double, from 80 to 150 million.