"We will continue to vigorously raise our concerns to the Iranian government."
Abdolsamad Khorramshahi, Saberi's lawyer, vowed to appeal the sentence.
Saberi, who has US and Iranian nationality and has lived in Iran for six years, has been detained in the Evin prison in Tehran since she was arrested in January.
She has reported for the US-based National Public Radio, the BBC and Fox News.
Her press credentials were revoked in 2006 and she was initially accused of working "illegally", but last week the charge was changed to that of spying for foreigners.
Iran and the US have been locked in a dispute over Iran's nuclear programme, which the US warns could be used to manufacture nuclear weapons.
Iran insists its nuclear programme is for purely civilian purposes.
Obama has said he wants to engage Iran in talks on its nuclear programme and other issues, a departure from the approach of the previous US administration, and it is unclear how Saberi's case will affect those plans.
Seyed Mohammad Marandi, a professor of American Studies at the University of Tehran, told Al Jazeera that the real blame lay with the US administration and its poor relations with Tehran.
"When the United States spends tens of millions of dollars a year to bring about regime change in Iran ... and there are hundreds of thousands of American forces in Afghanistan and Iraq and the US navy is just to the south of Iran, it's obvious that the Iranians are going to be more suspicious about activities carried out by people affiliated to the United States," he said.
"So the real culprit is the US government, and the government must, to decrease the amount of tension between the two countries and to decrease suspicion, they must abandon this unjust law."
'She was deceived'
Reza Saberi, Roxana's father, said that his daughter had been coerced into making incriminating statements about herself that she later retracted.
"She was deceived," he said on America's National Public Radio.
"She is quite depressed about this matter and she wants to go on a hunger strike. And if she does, she is so frail it can be very dangerous to her health."
Last month, Saberi's parents appealed to Ayatollah Ali Khamenei, the Iranian supreme leader, for her release, saying she was in a "dangerous" mental state.
Robert Mahoney, the deputy director of the Committee to Protect Journalists, told Al Jazeera that the exact details of the charge have not been made known to Saberi, her lawyer, or the public.
"It is very difficult for her lawyer - or for anyone - to defend her when we do not know exactly what she is accused of," Mahoney said.
"We are trying to mobilise the journalism community around the world to appeal to the Iranian leadership to release Ms Saberi on bail, pending an appeal."
Human rights groups have repeatedly criticised Iran for arresting journalists and suppressing freedom of speech.
The government has arrested several Iranian-Americans in the past few years, accusing elements of trying to overthrow it through what it calls a "soft revolution", but they were never put on trial and were eventually released.
This is the first time Iran has found an American journalist guilty of spying.