A fellow dual national prisoner will go on a hunger strike in an Iranian jail in solidarity with British-Australian academic Kylie Moore-Gilbert.
Ms Moore-Gilbert started a hunger strike in Tehran's Evin Prison on Tuesday after losing an appeal against a 10-year jail sentence for espionage.
She has been imprisoned since October 2018.
On Sunday, it was reported that Nazanin Zaghari-Ratcliffe, a British-Iranian mother jailed in Tehran since 2016 on sedition charges will now also refuse food.
Ms Zaghari-Ratcliffe's husband Richard Ratcliffe said: "five days on dry hunger strike is becoming critical, and our thoughts go out to Kylie and her family for all this ordeal".
Iran has announced Kylie Moore-Gilbert 'must serve her time'. Source: Supplied
"I hope the Australian and British governments also step up today and shake off the complacency of their holiday heads. It is one thing for the Iranian regime to hold innocent people hostage, it is quite another to let them die," he said, according to the Guardian.
Another jailed academic, French-Iranian Fariba Adelkhah, also begun a hunger strike on Christmas Eve.
An undated family handout file photo of jailed mother Nazanin Zaghari-Ratcliffe with her husband Richard Ratcliffe and their daughter Gabriella. Source: AAP
In an open letter published by supporters, the two women said: "We will strike on behalf of all academics and researchers across Iran and the Middle East, who like us have been unjustly imprisoned on trumped-up charges and simply doing their job as researchers.
"We have been subjected to psychological torture and numerous violations of our basic human rights."
When asked by reporters if he was concerned for Ms Moore-Gilbert's welfare, Prime Minister Scott Morrison said he was, adding: "As I am for any Australian who finds themselves in these types of situations."
But Iranian Foreign Ministry spokesman Seyyed Abbas Mousavi said Ms Moore-Gilbert is being afforded her legal rights.
"She has been arrested on a charge of violating Iran's national security, and the competent court has also issued the appropriate ruling by observing all relevant laws," he said.
"Experience has shown that the Islamic Republic of Iran would not give in to the political and smear campaigns, and this Australian citizen is serving her sentence while enjoying all legal rights, like any other convict with a judicial verdict."
On Friday, Minister for Foreign Affairs Marise Payne told SBS News: "This is a matter of deep concern to the government and to me personally as foreign minister".
"Since Dr Moore-Gilbert was detained, the Australian Government has consistently called on the Iranian Government to release her," she said.
Ms Moore-Gilbert was most recently a lecturer in Islamic Studies at Melbourne University.
The university's website lists her as specialising in Middle Eastern politics, with a particular focus on the Arab Gulf states.
It says she's had work published on the 2011 Arab uprisings, authoritarian governance and the role of new media technologies in political activism.
With additional reporting from AAP
