Imprisoned Americans Shane Bauer, left, Sarah Shourd, centre, and Josh Fattal were allowed to see their mothers last May at a hotel in Tehran. ((Press TV/Associated Press))

Iranian authorities plan to release jailed American Sarah Shourd on $500,000 US bail because of health problems, Iran’s judiciary announced Sunday.

Shourd is one of three Americans arrested after crossing into Iran on July 31, 2009. The others are Shane Bauer and Josh Fattal.

The three are in Tehran's Evin prison, accused of illegally crossing the border and espionage.

They had been hiking in the mountains of Kurdistan, which span the border between Iraq and Iran. Their families say the University of California, Berkeley graduates accidentally strayed over an unmarked border.

Shourd, 31, has been in solitary confinement, while the men have been sharing a cell.

Breast lump, precancerous cells

Her mother has said her daughter is suffering from health problems, including a breast lump and precancerous cervical cells.

Masoud Shafiei, Shourd's lawyer, confirmed that the Tehran prosecutor has offered to let her out of jail on bail, on the condition that she returns to the Iranian capital for a trial. Shafiei said he was hopeful that she would leave prison in the next two or three days, and he was confident she could leave Iran as soon as bail was posted.

The latest development comes amid confusion over the intentions of Iranian authorities.

President Mahmoud Ahmadinejad personally intervened to get Shourd released as an act of clemency at the end of the holy month of Ramadan, according to state media. However, the judiciary blocked plans to let her go just hours before her planned release on Saturday.

With files from The Associated Press