But, he said, advocates for the prisoners from within and outside Iran are trying to ensure a proper defense for the 13, who range in age from 16 to 49. They could face the death penalty.

Kermanian said an official request has been sent to the Iranian government requesting legal representation for the prisoners.

"We are awaiting the response of the government of Iran in that regard," Kermanian said.

He said the head of Iran's Jewish community, Parviz Yeshayaii, had been in contact with "various authorities inside the country" on behalf of the prisoners.

Legal representation is not guaranteed in Iranian courts.