TEHRAN, Iran â€“ An American journalist jailed in Iran has been convicted of spying and sentenced to eight years in prison just days after she was tried behind closed doors, her lawyer said Saturday, dashing any hopes for her quick release. The verdict was the first time Iran has found an American journalist guilty of spying, and it was unclear how the conviction would affect recent overtures by the Obama administration for better relations and engagement with Washington’s longtime adversary. Roxana Saberi, a 31-year-old dual American-Iranian citizen, was arrested in late January and initially accused of working without press credentials. But earlier this month, an Iranian judge leveled a far more serious allegation, charging her with spying for the United States. She appeared before an Iranian court behind closed doors on Monday in an unusually swift one-day trial. Her lawyer was permitted to attend, but had declined to discuss any details. The Fargo, North Dakota native had been living in Iran for six years and had worked as a freelance reporter for several news organizations including National Public Radio and the British Broadcasting Corp. “Saberi has been sentenced to eight years in jail. I’ll definitely appeal the verdict,” lawyer Abdolsamad Khorramshahi told The Associated Press. It was not immediately known when she was convicted. The United States has called the charges against Saberi baseless and has demanded her release, and the conviction and prison sentence could put strains on efforts to improve ties. President Barack Obama has said it wants to engage Iran in talks on its nuclear program and other issues â€” a departure from the tough talk of the Bush administration. Iran has been mostly lukewarm to the overtures, but Iran’s hard-line president gave the clearest signal yet on Wednesday that the Islamic Republic was also willing to start a new relationship with Washington. In a speech, President Mahmoud Ahmadinejad said Iran was preparing new proposals aimed at breaking an impasse with the West over its nuclear program. But it was uncertain how Washington would react to Saberi’s conviction. On Thursday, the State Department said Saberi’s jailing was not helpful and that Iran would gain U. S. good will if it “responded in a positive way” to the case. North Dakota Senator Byron Dorgan called on the Iranian government to “show compassion” and release Saberi. “This is a shocking miscarriage of justice,” the Democrat said in a statement issued Saturday. Some conservative Iranian lawmakers played down Saberi’s conviction, saying the verdict would not affect any ongoing efforts to build trust between Washington and Iran. “Although there is a wall of mistrust between Iran and the United States, the judicial verdict won’t affect possible future talks between the two countries. The verdict is based on evidence,” said lawmaker Hosseini Sobhaninia. The United States severed diplomatic relations with Iran after its 1979 Islamic revolution and takeover of the U. S. Embassy in Tehran. Relations deteriorated further under the former President George W. Bush, who labeled Iran as part of the so-called “Axis of Evil” along with Saddam Hussein’s Iraq and North Korea. Iran’s judiciary is dominated by hard-liners, which some analysts say are trying to derail efforts to improve U. S. -Iran relations. Saberi’s conviction comes about two months ahead of key presidential elections in June. Ahmadinejad is seeking re-election, but the hard-liner’s popularity has waned as Iran’s economy struggles with high-inflation and unemployment. The June 12 vote is pitting the hard-liners against reformists â€” led by a former prime minister Mir Hossein Mousavi â€” who support better relations with the U. S. Human rights groups have repeatedly criticized Iran for arresting journalists and suppressing freedom of speech. The government has arrested several Iranian-Americans in the past few years, citing alleged attempts to overthrow its Islamic government through what it calls a “soft revolution. ” But they were never put on trial and were eventually released from prison. Journalist watchdog groups criticized the conviction. The New York-based Committee to Protect Journalists said in a statement on Saturday that her trial “lacked transparency. ” “We call on the Iranian authorities to release her on bail pending her appeal,” Mohamed Abdel Dayem, the group’s Middle East and North Africa program coordinator, said in the statement. Iran has released few details about the charges against Saberi. Iranian officials initially said she had been arrested for working in the Islamic Republic without press credentials and she had told her father in a phone conversation that she was arrested after buying a bottle of wine. An Iranian investigative judge involved in the case charged that Saberi was passing classified information to U. S. intelligence services. Her parents, who traveled to Iran from their home in Fargo in a bid to help win their daughter’s release, could not immediately be reached for comment on Saturday. Her Iranian-born father, Reza Saberi, has said his daughter, who was Miss North Dakota in 1997, had been working on a book about the culture and people of Iran, and hoped to finish it and return to the United States this year.