Former US Ambassador to the UN Bill Richardson Sunday stated in an exclusive to CNN that WNBA star Brittney Griner and former US Marine Paul Whelan could be released from Russian detention following meetings he held with senior Russian officials.

Richardson visited Russia on behalf of Griner, Whelan and other American detainees in Russia. Richardson and his team work for a private humanitarian foundation, rather than for the US. Nonetheless, he stated that he consulted with the US and Russian officials and is “cautiously optimistic” regarding negotiations for Griner and Whelan’s release.

Last month, Coordinator for Strategic Communications at the National Security Council John Kirby spoke out against Richardson, stating, “[p]rivate citizens cannot negotiate on behalf of the United States government.” Kirby said that the US is continuing discussions to secure Griner and Whelan’s release, and such discussions should occur only between governments.

Griner is currently serving a nine-year sentence in Russia after pleading guilty to drug possession and smuggling charges on July 7. Whelan was detained in Russia on December 28, 2021, on suspicion of espionage. A judge ruled in January that he must remain in Russian custody until his trial.