Iran’s Baha'i minority are being prevented from obtaining identity cards under new rules, depriving them of basic civil rights in another blow to the persecuted group.

Iranian authorities have removed the Baha'i faith from the list of recognised religions on the new national ID card, which lists only Islam, Christianity, Judaism and Zoroastrianism as options.

A core tenet of the Baha'i faith is upholding the truth, which would prevent followers from lying on the form about their religion.

Without the card, Iranian nationals are unable to obtain credit cards, driver's licenses and passports. ID cards are also required to apply for a loan, cash cheques and buying property.

The UN says there are about 350,000 Baha'i followers in Iran, making them the country’s biggest religious minority.

They say hundreds of followers have been jailed or executed since Iran’s revolution in 1979.

“Before, the Baha’i used to tick the box ‘Other’, and while their religion wasn’t officially recognised, it was sufficient,” Padideh Sabeti, a spokesperson for the Baha'i International Community, told The Sunday Telegraph. “Now they have deliberately eliminated the option so the Baha’i - the country’s largest minority - is not recognised.

“We’ve heard from some inside Iran who have told us they have gone to get a new ID card and the official ticked Muslim for them on the form,” said Ms Sabeti, who speaks for the community in Iran from the UK. “When the person then asked them to change this, saying they were not Muslim but Baha’i, they were told they were not allowed.

“They are using this mechanism to deny the existence of the Baha’i, they can use the forms to tell the world that there are no longer any Baha’i in Iran,” said Ms Sabeti, who said applicants had been told that the changes to the forms had been ordered by the “powers on high”. “It’s a terrifying prospect.”

The religion started in Iran, but it has rapidly expanded since its founding and now has an estimated six million followers worldwide.

While Iran systematically discriminates against other religious minorities within its borders as well, the plight of the Baha'i community has been particularly well documented because of the group's size and the severity of the persecution to which it is subjected.

A United Nations report found that Baha'is have suffered from “the most egregious forms of repression, persecution and victimisation."