Political rivals have formed a political alliance to highlight the persecution of Iran's Baha'is.

Mark Coulton reckons the people of Dubbo know more about the plight of Baha'i Iranians than the politically-aware residents of Canberra.

The Nationals MP has formed a rare political alliance with a Labor MP who represents a large slice of the national capital.

He's a grazier representing the interests of a conservative western NSW community while Labor's Gai Brodtmann is a former public servant who worked on the Iran desk at the Department of Foreign Affairs.

Together they have sponsored a parliamentary motion condemning the treatment of Baha'is in Iran.

Mr Coulton describes their persecution of the past 30 years as something out of the "dark ages".

"People are imprisoned, not for committing a crime, but for belief in education, equal rights for women and support for a religion that only preaches peace and goodwill," he told parliament on Monday.

Mr Coulton said it was not without some irony that the people of Dubbo probably knew more about the persecution of the Baha'is than most other Australians.

That's because one of their own - businessman Nasser Sedghi - has been a vociferous advocate for the Baha'i cause.

It's also personal. Mr Sedghi's brother Farhad is imprisoned in Iran for his role with the Baha'i Institute for Higher Education, an underground organisation that provides education for those excluded from university by authorities.

"It's hard to believe in the 21st century that we have this sort of persecution taking place," Mr Coulton said.

Ms Brodtmann said since the 1979 Islamic revolution in Iran, Baha'is had been systematically persecuted as a matter of government policy.

During the first decade of their persecution more than 200 were killed or executed, hundreds more were tortured or imprisoned and tens of thousands lost their jobs, access to education and other rights.

Since 2005 about 700 Baha'is had been arrested and more than 100 were in prison. Nearly 50 homes had been targeted by arsonists.

Ms Brodtmann said denying access to higher education was a human right violation of the worst kind.