SYDNEY • Freed Australian-British academic Kylie Moore-Gilbert said yesterday that her release from jail in Iran ended a "long and traumatic ordeal", thanking those who campaigned for her freedom.

Dr Moore-Gilbert said the support she received while detained "had meant the world to me" and praised the government for "working tirelessly" on her behalf, according to a statement released by Australia's Foreign Ministry.

The academic, who is in her early 30s, also said she had "nothing but respect, love and admiration" for Iran and its people - despite spending two years and three months in prison on spying charges that she has strenuously denied.

"It is with bittersweet feelings that I depart your country, despite the injustices which I have been subjected to," she said. "I came to Iran as a friend and with friendly intentions, and depart Iran with those sentiments not only still intact, but strengthened."

She said she now faces a "challenging period of adjustment".

Dr Moore-Gilbert, a lecturer in Islamic studies at the University of Melbourne, had been serving a 10-year sentence for spying.

Iran confirmed her arrest in September last year but it had long been believed that she was detained a year earlier.

The Islamic Republic said on Wednesday that she had been released in a prisoner exchange but there was no immediate confirmation of the identity of the three Iranians reportedly involved.

Australian Prime Minister Scott Morrison yesterday said he had spoken with Dr Moore-Gilbert ahead of her return.

"I have always believed in miracles and I'm just thankful for this one," Mr Morrison told reporters.

"She seems to be, in our own conversations, in quite good spirits, but I imagine there is a lot of processing to go through yet."

Once Dr Moore-Gilbert arrives in Australia, she will go into quarantine at an unspecified location for two weeks.

AGENCE FRANCE-PRESSE, REUTERS