The American diplomat who welcomed WNBA star Brittney Griner onto the U.S. plane following a prisoner exchange for convicted Russian arms dealer Vitkor Bout described the experience of flying home with the pro-athlete. 

US Special Envoy for Hostage Affairs Roger Carstens, who fled to the United Arab Emirates and welcomed Griner on the tarmac, relayed his conversations with Griner during an appearance on CNN’s "State of the Union" Sunday. 

"It’s always kind of an exciting moment when you jump on the other country’s plane and walk up to a person and, in this case, Brittney. And I’ll tell you what I told her, ‘Brittney, my name is Ambassador Roger Carstens. I’m with the U.S. Department of State. And on behalf of the President of the United States, Joe Biden, and Secretary of State Tony Blinken, I’m here to take you home,’" Carstens told CNN host Dana Bash. "And at that moment, I think every person starts to realize that it’s going to happen – it’s setting in. Certainly, Brittney felt that way." 

"When she finally got onto the U.S. plane. I said, ‘Brittney, you must have been through a lot over the last ten months. Here's your seat. Please feel free to decompress. We'll give you your space.’ And she said, ‘Oh, no. I've been in prison for ten months now, listening to Russian. I want to talk. But first of all, who are these guys?’" Carstens said. "And she moved right past me and went to every member on that crew, looked them in the eyes, shook their hands and asked about them, got their names. Making a personal connection with them. It was really amazing." 

RUSSIAN STATE TELEVISION MOCKS US FOR BRITTNEY GRINER PRISONER EXCHANGE 

On the 18-hour flight, Carstens estimated Griner spent about 12 hours just talking. Griner was arrested in February before Russia invaded Ukraine for bringing in vape cartridges containing oils derived from cannabis through a Moscow airport as she was returning to the country to play for a basketball league. 

"I was left with the impression that this is an intelligent, passionate, compassionate, humble, interesting person, a patriotic person, but above all, authentic," Carstens said. "I hate the fact that I had to meet her in this manner, but I actually felt blessed having had a chance to get to know her."

Asked what Griner said of her 10-month ordeal being held in a Russian penal colony, Carstens said he "would hate to steal her thunder" in relaying too much of her story but that she spoke at length about the experience. 

Regarding her physical health, Carstens said Griner "looks fantastic" and was "full of energy" on her plane ride back to the United States. She is now at Fort Sam Houston undergoing medical evaluation at the major U.S. Army installation but "seems to be just fine," Carstens added. 

"What's that like to be the person to shake someone's hand and welcome them back to America after they've been wrongly held?" Bash asked Carstens. 

"It's humbling. It's I'm very grateful that President Biden allows me a chance to do this job. It's also a painful job," he responded. "So when you get the chance to shake someone's hands, it's one of those rare moments that you get to celebrate a victory. But know this, even as we're welcoming someone home, we still have work to do. So as I'm shaking Brittney's hands and we're taking to the aircraft and having this great conversation, my brain is already thinking about Paul Whalen. What can we do to get him back? What's our next move? What's the strategy? How can we adapt?" 

Carstens defended the swap despite criticism from Sen. Bob Menendez, D-N.J., who argued trading Griner for Bout incentivizing bad actors to kidnap Americans. 

Despite frustration, the trade wasn’t secured for former U.S. Marine Paul Whelan instead, the diplomat said the Biden administration is still actively working to return Whelan home. 

"I talked to him on Friday, the day after the swap. And here's what I told him," Carstens said. "I said, ‘Paul, you have the commitment of this president, the president's focus, the Secretary of State's focused. I'm certainly focused. And we're going to bring you home.’ And I reminded him, I said, ‘Paul, when you're in the Marines and I was in the Army, they always reminded you, keep the faith. And I said, keep the faith. We're coming to get you.’" 

The James Foley Foundation says that there are at least 60 Americans wrongfully detained across the globe. That includes Austin Tice, a former journalist and a former Marine who was kidnaped in Syria more than a year ago. In the past nine months, Carstens has helped bring home 15 Americans who were wrongfully detained or held hostage, and he says he’s been in frequent communications with Rice’s mother. "Again, hate to get into negotiations and things that we're currently doing, but as I've often told Deborah, Tice's mother, I'm optimistic," he said. "I think there are always paths forward that allow us to get an opportunity to bring someone like Austin home." 

In an appearance on MSNBC’s "The Sunday Show," former UN ambassador and governor of New Mexico Bill Richardson, who helped in getting Griner out, said Whelan must be next. Through his organization, Richardson also helped get former Marine Trevor Reed out of Russia about five months ago. 

"Well first, the Russians are extremely tough negotiators, and they’re very mad at us. The relationship between Russia and the U.S. over Ukraine and other issues obviously affects humanitarian decisions like an exchange of prisoners," Richardson said. 

During the Trump administration, National Security Adviser John Bolton handled a proposal by the Russians to trade Bout for Whelan, but the deal fell through, and Whelan has been incarcerated for the past four years unjustly, Richardson noted, adding, "We have to get Whelan out." 

"Sometimes it takes tough decisions. Like bringing back Bout, who’s a bad guy, but it has to happen."