TEHRAN - An Iranian-American journalist has gone on trial in Iran for spying for the United States and a verdict is expected soon, the judiciary said on Tuesday.

Washington says the charges against Roxana Saberi, who has reported for the BBC, National Public Radio and other media, are baseless and has demanded her immediate release.

Saberi's case coincides with talk of a possible thaw in U.S.-Iranian ties after new U.S. President Barack Obama offered a new beginning of engagement if Tehran unclenches its fist.

Judiciary spokesman Alireza Jamshidi told a news conference her trial started on Monday in a Revolutionary Court, which handles state security matters.

I think the verdict will be announced soon, perhaps in the next two or three weeks, he said. Her charge was spying for foreigners ... She had spied for the United States.

Under Iran's penal code, espionage can carry the death penalty. The Islamic Republic last year executed an Iranian businessman convicted of spying on the military for Israel.

Saberi, 31, is a citizen of both the United States and Iran but Tehran does not recognize dual nationality. It announced the espionage charges against her last week.

Jamshidi said Saberi, a freelance reporter who was born in the United States, had submitted the last defense arguments on her case. She was arrested in late January for working in Iran after her press credentials had expired.

The United States said the charges against Saberi were baseless and without foundation.

Jamshidi said: Giving an opinion on a case, by an individual or a government, without being informed about the facts in it, is utterly ridiculous.

VELVET REVOLUTION

Saberi's lawyer was not available for comment on Tuesday.

Her parents visited her in Tehran's Evin jail on April 6, after arriving from the United States. Evin is a jail where rights groups say political prisoners are usually taken.

Washington cut ties with Iran shortly after the Islamic revolution in 1979 but Obama's administration is trying to reach out to Tehran following three decades of mutual mistrust.

Iran says it wants to see a real switch in Washington's policies away from those of former President George W. Bush, who led a drive to isolate the country because of nuclear work the West suspects has military aims, a charge Iran denies.

On Monday, Iran said it would welcome dialogue with six world powers, including the United States, which had invited Iran to a meeting on the long-running nuclear row.

In another case that has caused concern in the West, Jamshidi said a higher court had upheld a three-year jail sentence against Silva Harotonian.

A diplomatic source said Harotonian was an Iranian citizen who worked for a U.S.-based non-governmental organization in Armenia and was detained while visiting Iran in 2008.

She was accused of involvement in a U.S.-funded plot to overthrow its Islamic system of government, along with two Iranian doctors who were jailed for three and six years respectively.

Iran often accuses the West of seeking to undermine the Islamic state through a soft or velvet revolution with the help of intellectuals and others inside the country.

Diplomats and human rights groups say Iran has cracked down on dissenting voices since President Mahmoud Ahmadinejad came to power in 2005, possibly in response to Western pressure on Tehran to halt its disputed nuclear work.

(Editing by Katie Nguyen)

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