Four Americans and seven Iranians were set to be exchanged in a deal linked to the imminent implementation of a landmark nuclear deal between Tehran and six world powers. Here's what we know about who they are. (Jason Aldag/The Washington Post)

Four Americans and seven Iranians were set to be exchanged in a deal linked to the imminent implementation of a landmark nuclear deal between Tehran and six world powers. Here's what we know about who they are. (Jason Aldag/The Washington Post)

A plane carrying Washington Post correspondent Jason Rezaian and two other Americans released by Iran landed in Germany on Sunday, a day after the implementation of a landmark agreement on Iran’s nuclear program.

In a brief phone call with the Washington Post‘s executive editor, Martin Baron, and the foreign editor, Douglas Jehl, from a U.S. military hospital in Germany, Rezaian said that he was feeling well both physically and mentally and was looking forward to being reunited with friends and family soon after undergoing medical tests.

Rezaian, who was released after 545 days in Tehran’s notorious Evin prison, said that the support of his family and colleagues during his incarceration had “meant everything.”

Asked how he was feeling, he added: “I’m a hell of a lot better than I was 48 hours ago.”

Once the Americans had left Iran aboard a Swiss aircraft, the Obama administration announced new sanctions related to participation in Iran’s ballistic missile program. The sanctions, which applied to 11 persons and companies, were issued under U.S. restrictions that remain in place despite the lifting Saturday of international sanctions tied to Iran’s nuclear program.

The Swiss plane landed in Geneva for a brief stopover before the Americans were flown to Germany for medical checkups at a U.S. military hospital. They landed at Ramstein Air Base shortly before 2 p.m. EST and were taken to the U.S. military’s nearby Landstuhl Regional Medical Center.

While the freed Americans were airborne, President Obama hailed the implementation of the nuclear agreement and the prisoner deal with Iran that led to their release. In televised remarks Sunday morning from the White House, he said that although “profound differences” remain between Washington and Tehran, the Iranian people now have a chance to end their isolation and “begin building new ties with the world.”

After the Americans arrived in Germany, Obama telephoned Ali Rezaian, Jason’s brother, who had arrived ahead of time in Landstuhl.

Ali Rezaian said Obama told him that his brother’s detention had lasted “too long.” In a call that lasted about two minutes, the president also said he hoped that Ali would be able to see Jason soon.

Ali Rezaian was not immediately able to see his brother but was able to speak to him on the phone. The three freed Americans were moved directly into the hospital for medical checks. Ali Rezaian was able to greet his mother, Mary Rezaian, and Jason’s wife, Yeganeh Salehi, who left Tehran on the Swiss plane.

In the telephone call with the Post’s editors, Rezaian said that isolation was the most difficult part of his time in prison. Still, snippets of information had made it back to him, lamong them that his Christmas greetings conveyed via his mother from prison had “made the rounds and reached everybody, which is what I intended.”

He also said that he found escape in the novels that he was allowed to read while in prison facing trial for spying.

President Obama said despite diplomatic progress made with Iran, there remain "profound differences" between the U.S. and Iran. He announced new sanctions on Iranians involved in ballistic missile program. (The White House)

Rezaian’s health was reported to have suffered from poor conditions at the prison and a lack of medicine for his high blood pressure. Family members earlier this year said that he had lost weight and suffered from back pain, and chronic eye and groin infections.

He told the editors in the early Monday phone call that his health had improved in the last several months. He is expected to face a battery of medical tests in the coming days, and it is not yet clear how long he will spend at the military hospital in Landstuhl.

[Transcript of Obama’s remarks on Iran nuclear deal and prisoner swap]

In Tehran, President Hassan Rouhani told the Iranian parliament that the end of nuclear-related sanctions marks a “turning point” for the country. He later proclaimed in a news conference that financial institutions in Iran would be able to reengage “the banks of the world for financial and monetary purposes.”

U.S. and European officials lifted the harshest economic sanctions against Tehran after the United Nations’ nuclear watchdog certified that the Islamic republic had fully complied with promises to curtail key parts of its nuclear program. Hours before diplomats in Vienna heralded the official activation of the nuclear deal, Iran confirmed the release of Rezaian and the other American detainees, set free in exchange for U.S. clemency offered to seven Iranians charged or imprisoned for sanctions violations and the dismissal of outstanding charges against 14 Iranians outside the United States.

The Post journalist boarded the flight to freedom Sunday after 18 months of captivity in Evin Prison, used for decades by both Iran’s Islamic revolutionary government and the monarchy it overthrew in 1979 to incarcerate — and, human rights groups say, abuse — political prisoners. He was tried in secret last year on charges including espionage and sentenced to an unspecified prison term.

Also on the plane were two other freed Iranian Americans — Saeed Abedini and Amir Hekmati. The plane left after an overnight delay stemming from what U.S. officials said was a misunderstanding among Iranian officials at the airport about the passenger manifest — specifically, whether Salehi and Mary Rezaian were supposed to be on the plane.

One of four Americans who were freed in the prisoner deal, Nosratollah ­Khosravi-Roodsari, did not fly out with the others, U.S. officials said.

[A misunderstanding held up the departure of 3 Americans]

“We can confirm that our detained U.S. citizens have been released and that those who wished to depart Iran have left,” a senior administration official said. “We have no further information to share at this time and would ask that everyone respect the privacy of these individuals and their families.”

A fifth American was released in a separate gesture by Iran and left Iran individually before the plane carrying the three Americans departed.

In his remarks Sunday from the Cabinet Room of the White House, Obama spoke of the ordeals suffered by the detained Americans. He called Rezaian “a courageous journalist . . . who wrote about the daily lives and hopes of the Iranian people,” adding: “He embodies the brave spirit that gives life to the freedom of the press.”

Obama said Iran “has agreed to deepen our coordination” in trying to locate former FBI agent Robert Levinson, who disappeared while visiting Iran’s Kish Island in 2007.

The seven Iranians being granted clemency in the deal “were not charged with terrorism or any violent offenses,” the president said. He described their release as “a one-time gesture to Iran” that reflects U.S. willingness to engage with the country “to advance our mutual interests.”

Although Iranian officials characterized the arrangement as an “exchange,” none of the seven who were granted clemency — six Iranian Americans and one with solely Iranian citizenship — were handed over to Iran, as in a traditional prisoner swap. Instead, U.S. officials said, they were free to decide individually whether to go to Iran.

At least five have chosen not to go, according to their lawyers.

Calling a recent missile test by Iran a “violation of its international obligations,” Obama said the United States as a result “is imposing sanctions on individuals and companies working to advance Iran’s ballistic missile program.”

The Treasury Department said the new sanctions apply to, among others, the Mabrooka Trading Co., based in the United Arab Emirates, and its networks based in that Persian Gulf country and in China. It said they have used front companies to deceive foreign suppliers about the true end-users of “sensitive goods for missile proliferation.”

[Photo gallery of scenes of arrival and anticipation]

Saturday’s coordinated moves to implement the nuclear deal and free prisoners cemented a major diplomatic victory for the Obama administration, which won significant nuclear concessions from Iran in an effort to defuse an international crisis that threatened to spark a new Middle East war. The agreement also frees Iran from crippling economic sanctions and opens the way for ending decades of diplomatic and economic isolation.

But the agreement also contains significant political risk for a White House that is staking its legacy on Iran’s willingness to comply with unprecedented curbs and extensive monitoring of its nuclear program. The pact — which has been repeatedly condemned by the Israeli government as well as by members of Congress from both parties — drew fresh attacks over the weekend from Republican presidential contenders, some of whom blasted the deal as a sellout to Iran’s clerical rulers.

In Jerusalem, Israeli Prime Minister Benjamin Netanyahu expressed his concern over Iran’s pivot away from international isolation. He asserted that Iranian leaders still harbor a desire to build atomic weapons but did not offer evidence to support that claim.

Iran’s supreme leader, Ayatollah Ali Khamenei, who wields ultimate political and religious authority in the Shiite Muslim theocracy, has said Iran does not want or need nuclear weapons, which he has declared to be forbidden by Islam.

“Even after the signing of the nuclear agreement, Iran has not relinquished its aspiration to obtain nuclear weapons,and it will continue to undermine stability in the Middle East and spread terrorism around the world while violating its international obligations,” Netanyahu said.

“Israel will continue to monitor the situation and warn about Iran’s negative activity, and will do everything necessary to safeguard its security and defend itself,” he said.

Saudi Arabia and other Arab opponents of Iran refrained from issuing such critical responses. But officials in Riyadh are deeply skeptical of the nuclear agreement: they fear that with billions of dollars of assets unfrozen by the accord, Tehran will be able to greatly expand its influence across the region.

In the Saudis’ view, such a development could affect the conflicts in Yemen, Syria and other countries where Saudi Arabia and Iran — fierce ideological and strategic rivals — use proxies to compete for influence.

The nuclear pact calls on Iran to disable key nuclear equipment in a deal designed to ensure that the country cannot accumulate enough fissile material to build a nuclear bomb. The agreement also requires unprecedented inspections and monitoring covering all aspects of Iran’s nuclear program, from uranium mining to research facilities.

Iranian Foreign Minister Mohammad Javad Zarif said on Twitter that “diplomacy requires patience, but we all know that it sure beats the alternatives.” Implementation of the deal, Zarif said, meant that “it’s now time for all — especially Muslim nations — to join hands and rid the world of violent extremism. Iran is ready.”

The release of prisoners had not been officially part of negotiations between Iran and the six world powers: the United States, Russia, China, Britain, France and Germany. But Kerry frequently raised the plight of imprisoned U.S. citizens during last year’s nuclear talks.

[Post coverage of Americans detained in Iran]

The Obama administration had come under heavy criticism for concluding the nuclear accord without winning the release of American detainees, including Rezaian, 39, whose 544-day detention was the longest for a Western journalist in Iran. White House officials confirmed that the prisoner deal was clinched during months of secret talks that gained momentum in the days before the nuclear pact was formally implemented Saturday.

“Friends and colleagues at The Washington Post are elated by the wonderful news that Jason Rezaian has been released from Evin Prison and has safely left the country with his wife, Yeganeh Salehi,” said Frederick J. Ryan Jr., publisher of The Post. “We are enormously grateful to all who played a role in securing his release. Our deep appreciation also goes to the many government leaders, journalists, human rights advocates and others around the world who have spoken out on Jason’s behalf and against the harsh confinement that was so wrongly imposed upon him,” he said.

“Now a free man, Jason will be reunited with his family, including his brother Ali, his most effective and tireless advocate. We look forward to the joyous occasion of welcoming him back to the Washington Post newsroom,” Ryan said.

In addition to Rezaian, the Americans freed Saturday included Abedini, 35, of Boise, Idaho; Hekmati, 32, of Flint, Mich.; and Khosravi-Roodsari.

A fifth American, identified as language student Matt Trevithick, was also released Saturday but was not part of the prisoner deal. Trevithick’s parents said in a statement that he had been held for 40 days in Evin Prison. A senior U.S. official said Trevithick, 30, left Iran on Saturday.

Abedini is a Christian pastor who had been imprisoned since July 2012 for organizing home churches. Hekmati is a former Marine who spent more than four years in prison on spying charges following his arrest in August 2011 during a visit to see his grandmother.

The detention of Khosravi-Roodsari had not been previously publicized. Iranian state television identified him as a businessman. Little else was known about him.

The arrangement quickly became political fodder in the United States among Republicans vying for the GOP presidential nomination.

In an appearance on “Fox News Sunday,” Sen. Ted Cruz (R-Tex.) said: “This deal is a very problematic deal, and it represents a pattern we’ve seen in the Obama administration over and over again of negotiating with terrorists.” He added: “I think it’s a very dangerous precedent because the result of this — every bad actor on Earth has been told: ‘Go capture an American.’ If you want to get terrorists out of jail, capture an American and President Obama is in the let’s-make-a-deal business.”

Republican front-runner Donald Trump said in a television interview that aired Sunday morning: “This should have happened years ago. . . . We’re giving them $150 billion. This shouldn’t be happening now. And I understand that in addition to the $150 billion, they’re getting hostages, also, or they’re getting some prisoners released. So I have to see what the deal is.”

Under the nuclear deal, Iran is recovering about $50 billion of its money that has been frozen in banks overseas, mostly in Asia, U.S. officials said.

Hillary Clinton, the Democratic front-runner, said Sunday on ABC’s “This Week” that she was “pleased, like I hope everybody is, that we have American citizens coming home this morning from Iran.” She said she had done “a lot of work on these issues” when she was secretary of state.

But Clinton said that “we have unfinished questions and business still” because of the disappearance of Levinson. “I think this is a part of what we’re going to be pursuing — persistent, patient diplomacy,” Clinton said.

Morello and Branigin reported from Washington. Hugh Naylor in Beirut, Ruth Eglash in Jerusalem and Karen DeYoung and Jose DelReal in Washington contributed to this report.

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