The wife of freed US reporter Jason Rezaian has described her harrowing 25-hour ordeal as she tried to leave Iran with her husband in an interview with the Washington Post.

In her first comments since Rezaian was freed from the notorious Evin prison where he spent 18 months on spying charges, Yeganeh Salehi told of how she feared she would not be able to leave the country with him as part of a prisoner swap.

Rezaian was among four prisoners freed in Iran on Saturday, just hours before world powers sealed a deal with Iran on its nuclear program. In return, the US pardoned seven Iranian prisoners and dropped charges against 14 other Iranians.

READ: Nuclear sanctions lifted as Iran, U.S. agree on prisoner swap

Salehi told the Post she and Rezaian's mother, Mary, spent hours being shuffled around various halls at Tehran airport by Iran's Revolutionary Guards until they were finally allowed to board a Swiss jet with him and the other freed prisoners.

"It was a real war to get me out," Salehi said in the interview, published Thursday, adding that she was unaware at the time that her being on the plane was part of the deal.

The Post said it was not clear if the ordeal stemmed from poor communication among the Iranians, or if the women were being used as a bargaining chip.

"The Iranians were playing games to the end," it quoted an unnamed senior US official saying.

Rezaian and his mother hold dual Iranian-US nationality while Salehi is Iranian, meaning it was not a given that she would be able to leave the country.

It was only after US Secretary of State John Kerry called his Iranian counterpart, Mohammad Javad Zarif, that the Iranian prosecutor general issued an order allowing Salehi and Mary Rezaian to board the plane to Germany, the Post reported.

Salehi said that, as she and Mary were being moved around the airport -- sometimes by guards covering their faces with surgical masks -- her mood swung from elation that her husband was to be freed to worry for her mother-in-law and herself.

"At some point I told her, 'Mary, somebody wants us out of the picture and there is a reason for it,'" Salehi said. "Something is wrong."

One of the four freed Iranian-Americans, former US Marine Amir Hekmati, returned to the United States on Thursday.