Iran ? An American journalist imprisoned on espionage charges in Iran for four months was freed Monday and reunited with her smiling, tearful parents — a move that clears a major obstacle to President Barack Obama’s attempts at dialogue with the top U.S. adversary in the Middle East.

The United States had said the charges against Roxana Saberi, a 32-year-old dual Iranian-American citizen, were baseless and repeatedly demanded her release.

Hard-line President Mahmoud Ahmadinejad could also win some domestic political points a month before he faces a re-election challenge from reformers who seek to ease Iran’s bitter rivalry with the United States.