Iran has said that Sarah Shourd, who has been held in the country for more than a year, will be released on compassionate grounds.

An Iranian government official said on Thursday that she would be allowed to leave to be with her mother who is suffering poor health.

Sarah Shourd is one of the three Americans being held in prison in Iran. She and the others have been there for more than a year on accusations of spying.

Shourd, Shane Bauer and Josh Fattal were arrested in July 2009 after straying into Iranian territory from Iraq.

The three said that they became lost on a hike in Iraqi Kurdistan.

US authorities have been demanding their release through the Swiss embassy in Tehran, which represents US interests in the country.

Reporters have been told to be at a Tehran hotel on Saturday morning to witness the release.