return from iran
U.S. Special Representative Brian Hook next to freed US student prisoner Xiyue Wang, who has jailed in Iran for 3 years Reuters

Barter seemed to have transpired recently between Iran and the United States. After being released from an Iranian jail in exchange for an Iranian scientist who was detained in the country, an American graduate student is back in the United States.

Saturday's release of Xiyue Wang, who was arrested in 2016 and sentenced to 10 years in prison for allegedly "infiltrating" the country and sending confidential materials abroad, highlighted the detention in Iran of at least four other Americans.

State Secretary Mike Pompeo confirmed on Saturday that returning Americans imprisoned in Iran and around the world is the top priority of the Trump administration.

The most notable detention is that of former FBI agent Robert Levinson, who in 2007, while on an unauthorized CIA mission, disappeared from the Iranian island of Kish.

The US has offered a $25 million reward for information leading directly to Levinson's safe location, recovery, and return. This is offered in addition to the $5 million reward that was already posted. Wang's release was welcomed by Levinson's family, although it was "bittersweet" news for their family.

Those imprisoned in Iran include Baquer Namazi, an 81-year-old businessman who has been held for more than two years and has been diagnosed with epilepsy. He's a former UN delegate for UNICEF Children's Agency, which served as governor of the oil-rich Khuzestan province of Iran under the US-baked shah.

He and his son Siamak Namazi, a dual national who has been detained for over three years, are serving a 10-year sentence after being accused of collaborating with a hostile power.

Another incarcerated US citizen is Navy veteran Michael White, who has been held since late July 2018 in an Iranian jail on unspecified charges. While meeting his Iranian wife, the 46-year-old White was arrested, his mother told the New York Times in January.

Tehran's Swiss Embassy looks out for the interests of America in the country like the US. Since the 1979 student uprising and the 444-day hostage crisis, the embassy there has been closed.

Karan Vafadari, an Iranian-American art dealer, and his Iranian mother, Afarin Nayssari, were sentenced to 27 years and 16 years in prison respectively.

On Saturday, Pompeo said that Wang was released as part of scientist Massoud Soleimani's exchange. Wang is now back in the US.

Since Trump unilaterally withdrew America from Tehran's nuclear deal with world powers in May 2018, tensions have been high between Iran and the United States. Since then, the US has imposed severe sanctions on the economy of Iran. The US has also blamed Iran for a series of attacks across the Mideast.

In the wake of Iran's unraveling nuclear deal with world powers, Western prisoners from the US and elsewhere will undoubtedly be used as bargaining chips in future negotiations.

In June, Iran released Nizar Zakka, a Lebanon-based US permanent resident who promoted internet freedom and worked for the US government. In September, the U.S. expelled Iranian Negar Ghodskani from Australia and was later sentenced to conspiracy to unlawfully export prohibited software from the US to Iran.