ISNA news agency quotes Aghajari as saying he was stopped from boarding the plane today.
Abdullah Momeni, a student activist accompanying Aghajari, was also banned from leaving.
Aghajari rose to prominence when he was sentenced to death for blasphemy after saying in 2002 that Muslims should not "blindly follow" religious leaders. He was cleared of the charge in 2005.
RFE/RL Iran Report
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