IDADI YA WATU WALIOSOMA HABARI HII: TEHRAN, Iran – An American journalist jailed in Iran has been convicted of spying and sentenced to eight years in prison, 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. 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 — a departure from the tough talk of the Bush administration.