The WNBA star, 32, was released from Russian custody in a prisoner exchange for a convicted arms dealer on Thursday, after spending nearly ten months under arrest.
In a statement given to media, per CNN, Paul's brother, David Whelan, said, "I am so glad that Brittney Griner is on her way home. As the family member of a Russian hostage, I can literally only imagine the joy she will have, being reunited with her loved ones, and in time for the holidays."
He added, "The Biden administration made the right decision to bring Ms. Griner home, and to make the deal that was possible, rather than waiting for one that wasn't going to happen."
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GMA/Twitter; KIRILL KUDRYAVTSEV/AFP via Getty From left: David Whelan and Paul Whelan
Still, David expressed in his message that he and his family are upset the same couldn't happen for his sibling, who has been held since 2018 for alleged espionage.
"Paul has worked so hard to survive nearly 4 years of this injustice," David said. "His hopes had soared with the knowledge that the US government was taking concrete steps for once towards his release. He'd been worrying about where he'd live when he got back to the U.S."
KIRILL KUDRYAVTSEV/AFP via Getty (2)
"And now what? How do you continue to survive, day after day, when you know that your government has failed twice to free you from a foreign prison? I can't imagine he retains any hope that a government will negotiate his freedom at this point," he continued. "It's clear that the U.S. government has no concessions that the Russian government will take for Paul Whelan. And so Paul will remain a prisoner until that changes."
"Increasingly, I worry that Paul himself won't survive 12 more years in a Russian labor colony. He has tried to stay healthy, but one wonders how long that determination to keep going can endure," David added, noting that "the likelihood that our parents will see their son again diminishes each day his wrongful detention continues."
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According to a U.S. official, Russia was only willing to negotiate for Griner and not Paul. The Biden administration still reportedly made numerous offers to get Paul back on U.S. soil, even after Russia explained they would only negotiate for the basketball star.
"It was a choice between bringing home one particular American — Brittney Griner — or bringing home none." They added that it was a "difficult decision" for President Joe Biden to make.
In a statement to CNN, Paul said, "I am greatly disappointed that more has not been done to secure my release, especially as the four-year anniversary of my arrest is coming up. I was arrested for a crime that never occurred. I don't understand why I'm still sitting here."
Though he noted to the outlet that he was happy Griner was released, he said he "was led to believe that things were moving in the right direction, and that the governments were negotiating and that something would happen fairly soon" for him as well.
Paul told CNN that he hopes Biden, 80, and his administration will "do everything they could to get me home, regardless of the price they might have to pay at this point," adding, "My bags are packed. I'm ready to go home. I just need an airplane to come and get me."
RELATED VIDEO: WNBA Star Brittney Griner Released from Russian Custody in Prisoner Swap
News of Paul's arrest broke on New Year's Eve 2018 when Russia's Federal Security Service (FSB) announced that it had detained the Michigan resident during a "spy mission." However, a U.S. government security source told PEOPLE at the time that Paul is not a secret agent for the United States.
During a Thursday morning press conference at the White House, Biden said his administration is continuing to fight for the release of Paul after that of Griner. "We never forgot about Brittney," he said. "We've not forgotten about Paul Whelan, who's been unjustly detained in Russia for years."
Biden added that Griner's release was "not a choice of which American to bring home," noting that the administration also successfully negotiated for the release of American Trevor Reed earlier this year. Reed — who was sentenced to nine years in a Russian prison in July 2020 for allegedly assaulting police officers — was released back to America in April in a different prisoner swap.
"Sadly, for totally illegitimate reasons, Russia is treating Paul's case differently than Brittney's," Biden said. "And while we have not yet succeeded in securing Paul's release, we are not giving up. We will never give up, but remain in close touch with Paul's family ... And my thoughts and prayers are with him today."