Reza Saberi told Reuters he spoke to 31-year-old freelance journalist Roxana Saberi by telephone early Tuesday morning.
"I am very worried. She is pretty suicidal," said the elder Saberi, who lives in Fargo, North Dakota. "She is saying she will go on a hunger strike if they keep her there. I tried to calm her down. I told her we are doing everything and to just hold on. Don't give in. We will try to secure her release."
Roxana Saberi has been jailed since Jan. 31 and was being held at Tehran's Evin prison.
Saberi said his daughter told him she had met with a prosecutor in Tehran and been told she may be in prison for several months and possibly up to two years.
U.S. Secretary of State Hillary Clinton has demanded that Tehran immediately release the journalist. And an official from the Iranian prosecutor's office said earlier this month that Iran's investigation of Saberi had been completed and she would be freed soon.
U.S.-born Saberi has worked for National Public Radio, the BBC, ABC News and other international media outlets.
An Iranian Foreign Ministry spokesman had said Saberi was working illegally after her press card was withdrawn two years ago.
Saberi's father said she was arrested ostensibly for buying a bottle of wine, which is banned under Iran's Islamic law.
He confirmed her credentials as a correspondent had been revoked, but said she had stayed in Tehran to pursue a master's degree and was doing research for a book about Iranian society. (Reporting by Carey Gillam, editing by Philip Barbara)
