Jason Rezaian, the Tehran bureau chief for The Washington Post, will be freed from an Iranian jail in a prisoner swap with the United States, U.S. officials confirmed today.

Rezaian, who was arrested in July 2014 on unspecified charges, has languished in prison during the intervening months on charges of espionage that observers say have no basis in fact. Experts speculated that Rezaian's imprisonment was part of a political calculus designed to give Iran leverage in the country's recent nuclear talks or intended as a bargaining chip for an eventual prisoner swap.

Three other U.S. prisoners will be released from Iran as part of the deal, according to The Washington Post.

U.S. officials confirmed news of Rezaian's release Saturday just before noon.

The Washington Post has not officially confirmed news of Rezaian's freedom as of noon Saturday. Washington Post publisher Fred Ryan said the news outlet is encouraged by word of his release.

"We couldn’t be happier to hear the news that Jason Rezaian has been released from Evin Prison," Ryan said. "Once we receive more details and can confirm Jason has safely left Iran, we will have more to share."

Ellen Nakashima, a Washington Post national security reporter, appeared to lend credence to the reports, noting that Rezaian will be "out of Iranian airspace in about 30 minutes." She later tweeted that the information came from lawyers for Iranians held in the United States and was not an official Washington Post statement.

Noting that today is Rezaian's 544th day in prison, press advocacy organization the Committee to Protect Journalists hailed the correspondent's release but noted that he should "never have been imprisoned in the first place."

"The farce of a judicial process that kept him in custody for 544 days has earned Tehran nothing but scorn from the international community," Sherif Mansour, CPJ's Middle East and North Africa program coordinator, said in a statement. "The Iranian government should begin taking steps immediately to improve its press freedom record by releasing all journalists imprisoned in relation to their work."

Rezaian's freedom would mean the conclusion of an ordeal that The Washington Post has by turns derided as "Kafkaesque" and "bogus." Since his arrest with his now free wife, Yeganeh Salehi, Rezaian has had limited access to his family and legal counsel. During his protracted detention, Rezaian's health reportedly worsened, battling chronic eye infections, back pain and groin inflammation, according to The Washington Post.

News of Rezaian's release comes as Secretary of State John Kerry meets with Iranian Foreign Minister Javad Zarif in Vienna, Austria.

Speaking from Vienna, Iran expert Hooman Majd said, "I think it shows that the more pragmatic and moderate authorities in Iran recognized, and were able to convince their hardline compatriots, how difficult it was going to be for Iran to be reintegrated into the world community—especially after the Saudi split—as long as these prisoners languished in jail."

"I also think it would have been awkward, after the attacks by the GOP candidates, for Obama to sign off on lifting sanctions on Iran as long as the prisoners were still behind bars. Perhaps Iran recognized that, as well," said Majd, a New York-based contributor to NBC News and Vanity Fair, who is in Vienna to help cover announcement of implementation of the Iranian nuke deal by Secretary State John Kerry and other diplomats.

There had been multiple theories over the past year as to how the case would be resolved, but most proved flat wrong. They've included the notion that the Post correspondent would be released as part of the international nuclear negotiations with Iran last year or during the subsequent September convening of world leaders at the UN General Assembly.

All the conventional wisdom was errant.

But when the journalist was sentenced last year after his secret "espionage" trial, Majd felt that that the lack of clarity about it was revealing. He still pointed to a desire among some in the faction-ridden Iranian government to at least figure out a swap of prisoners held in each country.

The government conspicuously noted that the sentence wasn't "finalized," which suggested they still wanted a way out.

Ultimately, the domestic U.S. politics were rather clear, especially given criticism of the Iranian deal by Republican presidential candidates: It would have been very awkward for Obama and Kerry to sign off on lifting the longtime economic sanctions against Iran, which was the case Saturday as they formally announce "implementation" of the deal, while the Americans were languishing in prison.

The GOP candidates, and many other administration critics, will still deride the basic deal. But the lingering presence of the jailed American would only have ramped up their doubts about the accord.

Now the frustrating diplomatic impasse appears over as the new nuclear deal kicks in.