Despite expecting to have the repatriation of failed asylum seekers raised during talks with Iran, Trade Minister Steve Ciobo says the topic never came up.

Mr Ciobo met with a number of Iranian ministers during a two-day visit leading a trade mission with Australian companies.

But he insists there were no discussions around Iran accepting the return of thousands of its citizens found not to be refugees in Australia.

"It wasn't raised," Mr Ciobo told AAP in Tehran on Wednesday.

By SBS