President Joe Biden, who signed off on the trade, confirmed during a morning news conference that Griner landed in the United Arab Emirates and was expected to be back in the U.S. within 24 hours. Biden, standing next to Griner's wife Cherelle Griner, said they spoke to the the basketball star by phone and she appeared in "good spirits."
"She's safe, she's on a plane, she's on her way home after months of being unjustly detained in Russia, held in intolerable circumstances," Biden said. "Britney will soon be back in the arms of her loved ones and she should have been there all along."
Get Boston local news, weather forecasts, lifestyle and entertainment stories to your inbox. Sign up for NBC Boston’s newsletters.
U.S. officials said she would be offered specialized medical services and counseling, but declined to go into specifics citing privacy concerns.
In her brief remarks, Cherelle Griner thanked the Biden administration for their efforts in securing her wife's release, saying she's "overwhelmed with emotions, but the most important emotion I'm feeling right now is gratitude."
"Today my family is whole," Cherelle Griner said.
Griner is a two-time Olympic gold medalist, Baylor University All-American and Phoenix Mercury pro basketball star, whose arrest in February made her the most high-profile American jailed abroad. Her status as an openly gay Black woman, locked up in a country where authorities have been hostile to the LBGTQ community, injected racial, gender and social dynamics into her legal saga and brought unprecedented attention to the population of wrongful detainees.
The swap, at a time of heightened tensions over Ukraine, achieved a top goal for President Biden, but carried a heavy price — and left behind Paul Whelan, a Michigan corporate security executive jailed for nearly four years in Russia on espionage charges that his family and the U.S. government has said are baseless.
Biden said the U.S. hasn't given up on Whelan and "we'll never give up" fighting to get him home.
"This was not a choice of which American to bring home," Biden said. "Sadly, for totally illegitimate reasons, Russia is treating Paul's case differently than Britney's."
“We will keep negotiating in good faith for Paul’s release," the president added.
More Brittney Griner Coverage:
Whelan's brother David said in a statement he was “so glad” for Griner's release but also disappointed for his family. He credited the White House with giving the Whelan family advance notice and said he did not fault officials for making the deal.
The Russian Foreign Ministry also confirmed the swap, saying in a statement carried by Russian news agencies that the exchange took place in Abu-Dhabi and that Bout has been flown home.
In releasing Bout, the U.S. freed a former Soviet Army lieutenant colonel whom the Justice Department once described as one of the world's most prolific arms dealers. He was arrested in Thailand in 2008 and extradited to the U.S. in 2010.
Bout, whose deeds were featured in a Hollywood movie, was serving a 25-year sentence on charges that he conspired to sell tens of millions of dollars in weapons that U.S officials said were to be used against Americans. Biden issued an executive grant of clemency to free the arms dealer from a federal prison in Illinois to effect the prisoner swap.
Griner was arrested at Moscow's Sheremetyevo Airport in February, when customs officials said they found vape canisters with cannabis oil in her luggage. She pleaded guilty in July, though still faced trial because admitting guilt in Russia's judicial system does not automatically end a case.
She acknowledged in court that she possessed the canisters, but said she had no criminal intent and said their presence in her luggage was due to hasty packing.
Before being sentenced on Aug. 4 and receiving a punishment her lawyers said was out of line for the offense, an emotional Griner apologized "for my mistake that I made and the embarrassment that I brought on them.” She added: “I hope in your ruling it does not end my life.”
In July, Secretary of State Antony Blinken revealed publicly that the U.S. had made a “substantial proposal” to Russia for Griner and Whelan. Though he did not specify the terms, people familiar with it said the U.S. had offered Bout.
The extraordinary public move during otherwise secret negotiations drew a rebuke from the Russians, who said they preferred to resolve such cases in private, and carried the risk of weakening the U.S. government's negotiating hand for this and future deals by making the administration appear too desperate. But the announcement was also meant to communicate to the public that Biden was doing what he could and to ensure pressure on the Russians.
Besides the efforts of U.S. officials, the release also followed months of back channel negotiations involving Bill Richardson, the former U.S. ambassador to the United Nations and a frequent emissary in hostage talks, and his top deputy, Mickey Bergman.
Late Thursday, the Griner family released a statement saying, in part: "We would like to extend our sincere gratitude to President Biden and his administration for the tireless work they did to bring Brittney home."