Update: Sunday morning: click here to read a newer version of this story.
Washington Post journalist Jason Rezaian, who has been detained in Iran since July 2014, will be released on Saturday as part of a prisoner swap deal, according to American and Iranian officials.
"We couldn't be happier to hear the news that Jason Rezaian has been released from Evin Prison," Washington Post publisher Frederick Ryan said in a statement. "Once we receive more details and can confirm Jason has safely left Iran, we will have more to share."
The swap is the result of 14 months of secret talks, which took place parallel to nuclear talks between Iran and the U.S.
Saturday was also a historic day in the nuclear agreement with Iran -- economic sanctions were lifted as international inspectors said Iran was complying with the agreements.
Secretary of State John Kerry said the prisoner swap was "accelerated" by the nuclear agreement.
"I am very happy to say that, as we speak, we have received confirmation that five Americans, who had been unjustly detained in Iran -- have been released from custody," Kerry said at a press conference.
Rezaian's family members said they were waiting for confirmation of his departure from Iran before commenting in detail.
"We all hope it is true," Rezaian's brother Ali wrote on Twitter, amid early news reports of a prisoner swap.
Rezaian has spent the past 18 months behind bars on charges of espionage that have been roundly denied by his colleagues and family members.
Analysts said he was treated like a pawn amid the nuclear negotiations and internal political battles in Iran.
The journalism advocacy group Reporters Without Borders said in a statement on Saturday, "We are thrilled to see Jason finally free, but he should have never been imprisoned in the first place. Jason was innocent. It is outrageous that he has been used as a bargaining chip."
Rezaian's so-called trial started last May and ended in August. In September, Iranian President Hassan Rouhani, in an interview with CNN's Christiane Amanpour, raised the prospect of a prisoner swap.
"If the Americans take the appropriate steps and set them free," Rouhani said, referring to Iranians who are being held in the U.S., "certainly the right environment will be open and the right circumstances will be created for us to do everything within our power and our purview to bring about the swiftest freedom for the Americans held in Iran as well."
In October, Rezaian was convicted by a Revolutionary Court in Iran. He was reportedly facing up to 20 years in prison. Post editor Marty Baron called the conviction an "outrageous injustice."
As time dragged on, some American politicians called Rezaian a "hostage." Doug Jehl, the Post's foreign editor, said last fall that it seemed like "Jason is not really a prisoner, he's a bargaining chip being used by the Iranian government to extract some concessions from the U.S."
Trial has been cloaked in secrecy
Journalists around the world repeatedly protested his detention and called for his release. Earlier this month, the leaders of media advocacy groups and 25 news agencies, including CNN, sent a letter to Secretary of State John Kerry urging the U.S. government to do more to secure Rezaian's release.
"Independent journalism is recognized as a fundamental human right. Iran should recognize this, too, and free Jason," the editors wrote.
Government officials have pressed Rezaian's case during negotiations about Iran's nuclear program.
John Kirby, a State Department spokesman, said earlier this month: "As we have said repeatedly, we believe that our citizens should be returned to the United States to be with their families as soon as they possibly can. As Secretary Kerry has noted many times, we are working very hard to get our citizens back home, and we call again on Iran to release them."