An Iranian scientist detained in the United States returned to Iran on Tuesday, a possible precursor to a prisoner swap between the countries despite his growing hostility since President Trump took office more than three years ago.
Iran's foreign minister, Mohammad Javad Zarif, said the scientist, Sirous Asgari, was on his way home, which Zarif described as "great news,quot; in an announcement on his Instagram account. A spokesman for the Iranian Foreign Ministry, Seyed Abbas Mousavi, told the Iranian media that Asgari would arrive in Tehran on Wednesday morning.
Mr. Asgari's release has been anticipated by Iranian officials. While they denied that his release was part of a prisoner swap, there have been indications that the United States would view it as a positive gesture that could help free at least one American held in Iran. At least four are known to be in custody.
Asgari was acquitted last November in federal court on charges of stealing trade secrets in violation of sanctions during a sabbatical visit to a US university in Ohio. ICE agents detained him for deportation after his case was dismissed.
He was infected with the coronavirus while detained in an ICE detention center in Louisiana, delaying his return home. US officials tried to send him back to Iran in March, flying around the United States nine times in an attempt to put him on a flight with connections to Iran, but pandemic blockades canceled almost all international air travel.
Speculation has continued that a 48-year-old US Navy veteran, Michael R. White, who has been incarcerated in Iran for nearly two years, may soon return to the United States once Mr. Asgari returns to Iran. Like Mr. Asgari, Mr. White was infected with the coronavirus while in custody.
White, a cancer survivor, had been visiting an Iranian woman he met online when he was arrested in July 2018 and later sentenced to a 10 years in prison on shady charges.
He was released from prison a few months ago when the coronavirus spread became a crisis in Iran. Swiss diplomats, acting on behalf of the United States in Iran, have been taking care of his case.
It was not clear Tuesday night whether there was any change in Mr. White's status in Iran.
Jonathan Franks, a spokesman for Mr. White's family, said he had no news of his impending release or any indication that Mr. Asgari's release would play a role.
In Washington, a senior State Department official said that nothing had changed with respect to Mr. White and that since his prison license he had been living under "whatever arrangement the regime resolved with the Swiss."
The prisoner issue has long been a volatile point of controversy in separate relations between Iran and the United States. Each has accused the other of retaining their citizens for political reasons.
The last significant prisoner release occurred when the nuclear deal with Iran negotiated by the United States and five other major powers took effect in January 2016. The administration resigned from that deal after Trump took office and relations have worsened since then. .
Rick Gladstone and Lara Jakes contributed reporting.