BEIRUT, Lebanon  Iran plans to release Sarah E. Shourd, one of the three American hikers detained last year and accused of spying, Iranian officials said Thursday.

The Ministry of Culture and Islamic Guidance in Iran has invited reporters to witness the release on Saturday morning at a Tehran hotel, the same hotel where the three Americans were allowed to meet with their mothers in May  their only meeting with relatives or other Westerners since they were detained after straying across the mountainous border with northern Iraq in July 2009.

The detention of the hikers  Ms. Shourd, 32, and Shane M. Bauer and Joshua F. Fattal, both 28  further strained relations between Iran and the United States, which have long been at odds over Tehran’s nuclear program.

Earlier this year, Washington imposed a new round of sanctions on Iran, as did the United Nations Security Council and the European Union. Iran maintains that it aims only to produce nuclear energy for peaceful purposes, but Western powers have long suspected that the Iranian program could be used to produce weapons and fuel a regional nuclear arms race.