US Secretary of State John Kerry has called on the Iranian government to \"work cooperatively\" with the US to return three American citizens to their families. In a statement last night, Kerry said Robert Levinson, Amir Hekmati, and Saeed Abedini must \"be reunited with their families safely and as soon as possible.\" Levinson went missing from Iran\'s Kish Island in 2007, while Hekmati and Abedini have been in Iranian prisons for two years and one year, respectively. Hekmati remains detained on what the US called \"false espionage charges\" and Abedini remains detained due to his unspecified religious beliefs. \"We urge the Iranian Government to release Mr. Hekmati and Mr. Abedini and to help us locate Mr. Levinson,\" said Kerry. \"These men belong at home with those who love them and miss them.\" Kerry also appealed to Iran\'s newly-elected leader and his promises of reform. \"President Rouhani has shared in his speeches and interviews over the past few months his hope and vision to improve the Government of the Islamic Republic of Iran\'s relationship with the world,\" he added.