WASHINGTON ― In the final weeks of Barack Obama’s presidency, administration representatives held secret negotiations with Iranian officials, aimed at securing the release of American citizens imprisoned in Tehran.

The talks, described publicly for the first time by a lawyer working on behalf of two of the prisoners, began in mid-December and collapsed days before President Donald Trump’s inauguration in January. Iranian negotiators, aware that the Obama administration was eager to strike a deal before leaving office, made unmeetable demands, said Jared Genser, a human rights attorney who has been in frequent contact with U.S. government officials about the effort to free the prisoners.

The Iranians “were not serious,” a State Department official told Genser, who declined to characterize Tehran’s demands in more detail. Genser represents Siamak Namazi and his father, Baquer ― both of whom are dual American-Iranian citizens and have been held in Evin prison for more than one year.

In addition to the Namazis, the Iran’s Islamic Revolutionary Guards Corps is holding U.S. citizens Reza “Robin” Shahini and Karan Vafadari, as well as U.S. lawful permanent residents Afarin Niasari and Nizar Zakka.

Babak Namazi, Siamak’s older brother and Baquer’s son, traveled to Washington, D.C., from Dubai this week to press the Trump administration to prioritize the release of his family members and highlight their deteriorating mental and physical condition in prison. State Department and White House officials said “all the right things” in meetings, Genser said, but emphasized that they were still developing a broader policy on Iran.

“The sole mission I have in life right now is to get the freedom of Siamak and my dad,” Babak told a small group of reporters on Thursday, after meeting with government officials and lawmakers. “I spend restless nights thinking, ‘Will I see my dad again? Will I see Siamak again? Are they cold? Are they hungry?’”

A State Department spokeswoman declined to comment on specific cases, citing privacy restrictions.

“The safety and security of U.S. citizens remains a top priority and we make all appropriate efforts to work for the release of any unjustly detained U.S. citizens held overseas,” she said in a statement. “We call for the immediate release of all U.S. citizens unjustly detained in Iran so they can return to their families.”

Siamak Namazi was apprehended at the airport in Tehran in July 2015, during what was supposed to be a short visit. Plainclothes members of the Revolutionary Guards confiscated his passport and interrogated him in a car outside the airport, Babak said. They let him go, but he could not leave the country and return home to Dubai. They repeatedly called him in for interrogations over the next several months, before finally arresting him in October 2015.

When the Obama administration reached an agreement with Iran in January 2016 to free four American citizens in exchange for seven Iranians held in the U.S., Iranian news outlets initially mistakenly identified Siamak as one of the Americans who would be released in the swap. Subsequent reports clarified that he was not included in the deal.

“We got blindsided in January,” Babak said of Siamak being left behind as other Americans returned home. Initial joy at seeing Siamak’s name in the incorrect media reports turned to horror, he said.

The Obama administration never gave the Namazi family a clear explanation of why Siamak was not included in the swap, according to Babak. Senior administration officials told reporters that the family asked for him to be left out, believing that Siamak, who hadn’t lived in the U.S. for years, had a better chance of getting out than some of the other Americans. Babak disputes those reports and is adamant that he made clear to the State Department that he wanted U.S. officials to negotiate his brother’s release.

Baquer traveled from Iran to Dubai to visit Babak in February. Once there, he received a call from Iranian officials. If he returned to Iran immediately, he would be granted a visit to Siamak. He jumped at the offer. But once landed in the Tehran airport, he was also arrested and taken to Evin. Last week marked the one-year anniversary of his imprisonment.

Siamak and Baquer were sentenced last October to 10 years in prison on charges of collaborating with the U.S. It is “practically a death sentence” for 80-year-old Baquer, Babak said when they were sentenced. Baquer, who has had triple-bypass surgery, was hospitalized several weeks ago, his son said. Siamak has spent much of his imprisonment in solitary confinement without a mattress to sleep on, according to Babak.

After the Namazis were sentenced, then-presidential candidate Trump tweeted about their case, indicating he would take a tough approach to Iran’s practice of arresting American citizens and holding them as bargaining chips. (There is no public record of Tehran asking for money in return for the Namazis’ release.)

Well, Iran has done it again. Taken two of our people and asking for a fortune for their release. This doesn't happen if I'm president! — Donald J. Trump (@realDonaldTrump) October 23, 2016

Although Trump is aware of the Namazis’ situation, there is no indication of whether — or how — he will work to bring them home. Trump criticized the last prisoner swap as uneven and took an aggressive tone on Iran throughout the campaign. But since his inauguration, he has backtracked on a previous promise to scrap the nuclear agreement with Iran that paved the way for the prisoner agreement.

Even if Trump is willing to strike a deal with Iran, it is unclear how his administration would go about negotiating it. Six weeks into his presidency, several top-level State Department positions are still vacant. Genser said a National Security Council official told him that Siamak and Baquer’s cases are “very high priority,” but also said that the administration’s policy on American hostages will have to be factored into their still-developing policy on Iran.

At this point, there is no communication between the Trump administration and the government of Iran, Genser said.

“We have no information to suggest that anything active is happening right now, and that has to change,” he added, urging the Trump administration to at least reach out to traditional intermediaries in Switzerland and Oman.

With Baquer’s deteriorating health, the two governments do not have much time to act. If the elderly American citizen were to die in an Iranian prison, it could precipitate an international crisis. Genser doesn’t want that to happen.

“The death of an American hostage in Iran,” he said, “would force decisions to be made by the [Trump] administration that would not be in the interests of the government of Iran ― or, frankly, the government of the United States.”

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