US President George W. Bush on Friday strongly condemned Tehran's detention of several US-Iranian dual nationals and called for their immediate and unconditional release.
"I strongly condemn their detention at the hands of Iranian authorities. They should be freed immediately and unconditionally," Bush said in a statement.
Journalist Parnaz Azima and academics Haleh Esfandiari, Kian Tajbakhsh, and Ali Shakeri were "being held against their will by the Iranian regime," he said. US and Iranian officials have said the three academics are being held in Iran on spying charges and that the journalist faced similar allegations but had not been arrested.
"These individuals have dedicated themselves to building bridges between the American and Iranian people, a goal the Iranian regime claims to support," Bush said. "Their presence in Iran - to visit their parents or to conduct humanitarian work - poses no threat," he said. "Indeed, their activities are typical of the abiding ties that Iranian-Americans have with their land of origin."
All four of the targeted dual nationals had been in Iran on private visits. Iran does not recognise dual nationality of its citizens and the State Department said it has ignored US requests for consular access to the four. The United States has not had diplomatic relations with Iran since shortly after the Islamic revolution in 1979.
Esfandiari heads the Middle East program at the Washington-based Woodrow Wilson International Center for Scholars. She returned to Iran in December to visit her ailing, 93-year-old mother, and has been jailed in Tehran's notorious Evin prison.
Tajbakhsh is an expert in urban planning who has taught in the United States and Iran and has worked for the World Bank as well as the Open Society Institute of US billionaire George Soros.