Levinson, a retired FBI agent, went missing from Kish Island, Iran, in March 2007.
Kerry`s statement called on the Iranian government to uphold its offer to help find him.
Iran has expressed doubts that Levinson is still on Iranian soil.
Kerry also called for information on dual US citizens Amir Hekmati and Saeed Abedini, both serving time in Iranian jails.
Thursday marks the two-year anniversary of Hekmati`s detention on what Kerry described as false espionage charges. Abedini, detained for nearly a year, was sentenced to eight years in prison on charges related to his religious beliefs.
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