President Biden Says Administration Is 'Not Giving Up' on Bringing Paul Whelan Home After Griner's Release

President Biden Says Administration Is 'Not Giving Up' on Bringing Paul Whelan Home After Griner's Release

Shortly after announcing the release of WNBA star Brittney Griner from Russian custody, President Joe Biden said his administration is continuing to fight for the release of another American imprisoned in Russia: former U.S. Marine Paul Whelan, who has been held since 2018 for alleged espionage.

News of Whelan'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.

RELATED: American Detained in Russia on Espionage Charges 'Is Not Our Spy,' Security Source Says

In July, a representative from the White House confirmed to PEOPLE that the Biden administration had "made a substantial proposal to bring Brittney Griner and Paul Whelan home weeks ago."

The negotiations involved the exchange of the Americans for a Russian prisoner in the United States, Viktor Bout, who was convicted for arms trafficking and was serving 25 years.

Speaking at the White House Thursday, Biden announced that 32-year-old Griner has been released from Russian custody in a prisoner exchange for the convinced arms dealer and is now "safe" and "on a plane."

Whelan, however, remains in Russia.

US President Joe Biden, Paul Whelan
US President Joe Biden, Paul Whelan

Jim Lo Scalzo/EPA/Bloomberg via Getty, KIRILL KUDRYAVTSEV/AFP via Getty President Joe Biden, former Marine Paul Whelan

RELATED: WNBA Star Brittney Griner Released from Russian Custody in Prisoner Swap

Griner was detained in Russia in February for allegedly smuggling "narcotic drugs" into the country and sentenced to nine years in prison on Aug. 10, just below the maximum allowed sentence of 10 years.

Griner, Biden said, first wrote to him in July but "didn't ask for special treatment." Instead, she asked for a one thing: that the president not forget about her and the other detainees.

RELATED: 'Forgotten' American Woman Jailed in Russia with Brittney Griner Tried to Flee with U.S. Help Before Arrest

Joe Biden; Brittney Griner
Joe Biden; Brittney Griner

Chris Kleponis/CNP/Bloomberg via Getty; Tim Clayton/Corbis via Getty

"We never forgot about Brittney," Biden 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 — received a trial that American ambassador to Russia John J. Sullivan called "so preposterous that they provoked laughter in the courtroom," noting that "even the judge laughed."

Reed was released back to America in April in a different prisoner swap, but Whelan's release has so far not materialized.

"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."

RELATED: President Joe Biden Meets with Brittney Griner and Paul Whelan's Family Members at the White House

Noting that Whelan's family likely had "mixed emotions today" with the news of Griner's release, Biden said his administration would keep negotiating "in good faith for Paul's release."

"I guarantee that I say that to the family," Biden said. "I guarantee you and urge Russia to do the same, to ensure that Paul's health and treatment [are] maintained until we are able to bring him home."

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The health of 52-year-old Whelan, who is being detained in a labor camp, is of top concern to his family members. His twin brother, David, told Good Morning America earlier this year that Paul had lost "about 20% of his weight" since he was first detained in December 2018 and is supplementing his prison meals with quarterly packages sent by his family that included dried fruit and nuts.

"We know that he is not being given proper nutrition because that's the normal diet in a Russian prison," he told GMA.

Cherelle Griner (L), wife of Olympian and WNBA player Brittney Griner, speaks after U.S. President Joe Biden announced her release from Russian custody, at the White House on December 08, 2022 in Washington, DC. Griner was released as part of a prisoner swap that involved Russian arms dealer Viktor Bout. Biden was joined by U.S. Secretary of State Anthony Blinken and Vice President Kamala Harris.

Chip Somodevilla/Getty

Griner's wife, Cherelle, offered her own remarks from the White House Thursday, saying, "Today my family is whole, but as you are all aware, there are so many families who are not whole."

She added that she will continue advocating for "getting every American home, including Paul, whose family is in our hearts today."

In a statement on Griner's release, Secretary of State Antony Blinken touched on the challenges facing the U.S. in its ongoing negotiations concerning Whelan.

"While we celebrate Brittney's release, Paul Whelan and his family continue to suffer needlessly," Blinken said in the statement. "Despite our ceaseless efforts, the Russian Government has not yet been willing to bring a long overdue end to his wrongful detention."

Blinken continued: "I wholeheartedly wish we could have brought Paul home today on the same plane with Brittney. Nevertheless, we will not relent in our efforts to bring Paul and all other U.S. nationals held hostage or wrongfully detained abroad home to their loved ones where they belong."