Blinken speaks to Paul Whelan, American wrongfully detained by Moscow: Sources

Secretary of State Antony Blinken spoke over the phone with Paul Whelan, a wrongfully imprisoned American citizen who has been jailed by Moscow since 2018, according to sources familiar with the call.

A source said that during their conversation on Wednesday, Blinken reassured Whelan, who is currently being held in a remote prison camp in Russia, that U.S. officials were doing everything possible to secure his freedom.

Whelan was also able to call his parents after speaking with Blinken, and relayed to them that he had "long, frank conversation" with the secretary, his brother David said.

The call marks the second time Blinken has spoken to Whelan during his nearly five years in detention.

Whelan is one of just two American citizens held by Russia known to be classified as unjustly detained by the U.S. government. The other is Wall Street Journal reporter Evan Gershkovich, who was arrested in March and accused of espionage. Gershkovich has pleaded not guilty and the Wall Street Journal has vehemently denied the allegations, calling the charges "categorically false" in April.

Blinken also revealed in March that the Biden administration had made a "serious proposal" to Russia for Whelan's release. But sources say that Moscow has yet to engage in any serious negotiations.

The Biden administration also attempted to bring Whelan home in negotiations that ultimately led to two separate prisoner swaps in 2018.

One exchange saw the U.S. free Konstantin Yaroshenko, a convicted drug smuggler, for former Marine Trevor Reed. In the second, the Biden administration traded Viktor Bout, a notorious Russian arms dealer, for WNBA star Brittney Griner.

In both deals, U.S. officials say they were forced to leave Whelan out of the agreement in order to free the other detainee.

Whelan, via his family, has previously expressed feelings of abandonment and concern that the U.S. will again choose to free another American detainee instead of him, according to his family.

In April, Whelan told CNN in a phone interview that he had received assurances that he would not be left behind.

"I have been told that I won't be left behind, and I have been told that although Evan's case is a priority, mine is also a priority," Whelan said at the time, according to CNN. "I feel that my life shouldn't be considered less valuable or important than others who have been previously traded."

Whelan is currently serving a 16-year sentence on espionage charges he and the American government say are fabricated.

After spending 18 months in pre-trial detention, Whelan was convicted by a Russian court in June of 2020 and transferred to Mordovia, a region about 300 miles east of Moscow known for its network of prisons, where he remains to this day.

ABC's Cindy Smith contributed to this report.