The letter, delivered on Friday, said there was no evidence to justify the detention of Siamak Namazi, who was “left behind” in the wake of a U.S.-Iran prisoner deal that saw other Americans released from Iranian jails last month.
“An American who has worked tirelessly as a bridge-builder of cultures, countries, and faiths is sitting in a prison in Tehran,” said the letter, which was signed by the National Iranian American Council, the Public Affairs Alliance of Iranian Americans and other groups. “We urge you to work tirelessly to pursue Siamak Namazi’s release.”
Namazi, who is based in Dubai, was visiting relatives in Iran when he was detained. Most recently, he was working for Crescent Petroleum, an oil and gas company in the United Arab Emirates, and previously, he headed a consulting firm in Iran.
“The U.S. government does everything and will continue to do everything it can on behalf of its citizens detained around the world who request our assistance,” Sam Werberg, press officer for the State Department’s Office of Iranian Affairs, told Reuters by email on Sunday.
Namazi’s family declined to comment.
Iranian officials have not announced any charges against Namazi. On Sunday, an Iranian judiciary official said there were several dual nationals being held in Iran on espionage charges, Iranian media reported.
The letter comes three weeks after four other Iranian-Americans, including Washington Post reporter Jason Rezaian, were released from prison by Iranian authorities. In return, U.S. authorities granted clemency to seven Iranians in the United States, and moved to drop international arrest orders and charges against 14 other Iranians outside America.
The release of the Americans came after extensive public campaigns waged by their family members and U.S. officials. On the sidelines of nuclear negotiations, U.S. diplomats “used every meeting to push Iran” to release the men, President Barack Obama said last month.
U.S. authorities have described the prisoner exchange as a “one-time, unique agreement” and said the United States has told Iran it does not expect to repeat the deal.
In a speech last month, Kerry said the United States was still working to find out what happened to Robert Levinson, a former U.S. law-enforcement agent who disappeared while visiting Iran in 2007. Kerry did not mention Namazi in his remarks.