Iranian officials said Saturday that Iran has put on hold the release of one of the three U.S. female hikers in custody, reversing an earlier announcement on the hiker's release.

Mohammad Hassan Salehimaram, an official from the information center of Iran's presidential office, said Saturday that "the release of an American... was postponed."

"The details (of postponement) will be issued later," Salehimaram was quoted by official IRNA news agency as saying.

Iranian Foreign Ministry spokesman Ramin Mehmanparast said Friday that the detained U.S. female hiker Sarah Shourd would be released soon to join her family.

"Discussions are still ongoing regarding the details and the date of her release," said Mehmanparast without giving further details as to when and where the hiker would be released, according to local satellite Press TV.

Meanwhile, Tehran Prosecutor General Abbas Jafari-Dolatabadi told Press TV on Saturday that judicial proceedings in the defendant's case have not been completed.

"Because the legal procedure of Sarah Shourd's case is not finished, her release is cancelled," he said without mentioning when the American woman would be released.

On Thursday, Iran confirmed earlier reports that it would release Sarah Shourd, one of the three U.S. hikers held in Tehran for over a year.

Also on Thursday, Iran's Islamic Cultural and Guidance Ministry told Xinhua in a text message that it would release one of the detained American hikers in Tehran on Saturday.

Reporters were invited to Esteqlal (Independence) Hotel in Tehran to cover the release of the hiker, according to the message.

The U.S. State Department then urged Iran to release all three hikers after Tehran announced it would release one of them on Saturday.

The U.S. State Department spokesman Mark Toner on Thursday urged Iran to release all three hikers, saying the U.S. government has called for their release "on humanitarian grounds for many, many months."

The three Americans, Sarah Shourd, Josh Fattal and Shane Bauer, were arrested in Iran on July 31 last year after they illegally entered the country from its western borders.

They were charged with espionage last November, which the U.S. government considered totally unfounded and said they should be freed.

In May, the mothers of the three Americans were allowed by the Iranian government to meet their children in Tehran.

In June, the 32-year-old Iranian scholar Shahram Amiri, who once worked at Iran's Malek Ashtar University and had gone missing on a pilgrimage in Saudi Arabia last year, arrived at Tehran's Imam Khomeini airport from the United States.

Media reports had said that the scholar was released by the U.S. to exchange the three Americans hikers, which was rejected by Iran.