Sulaiman Abu Ghaith, a Kuwaiti preacher, was allowed to return to Afghanistan following more than eight years of living under a modest form of house arrest in Iran, the online Long War Journal reports.
The report claims his release was part of an exchange with the Taliban for the release of Iranian diplomat Heshmatollah Attarzadeh, who was kidnapped in 2008.
The Long War Journal identifies the Kuwaiti cleric as a spokesman for bin Laden. In October 2001, the cleric released a statement saying the Sept. 11, 2001, attacks on the United States was "a good deed."
Kuwait stripped the cleric of his citizenship after the 2001 attacks.
The Times of London reported last year that several members of the bin Laden family, including one of his six wives, were living in Iran after fleeing Afghanistan in the wake of the 2001 attacks.
Bin Laden is believed to be hiding in the mountainous tribal provinces of northern Pakistan.