(NewsNation) — Russia confirmed on Thursday for the first time that it is in negotiations with the U.S. over a possible prisoner swap that would result in freedom for WNBA star Brittney Griner and Marine Paul Whelan, per media reports.

Russian Foreign Ministry spokesman Ivan Nechayev said Thursday that exchange negotiations began after Foreign Minister Sergey Lavrov confirmed last week that Russia was willing to talk, the Washington Post reported.

“Instructions were given to authorized structures to carry out negotiations,” Nechayev told journalists in Moscow on Thursday, according to the newspaper. “They are being conducted by competent authorities.”

Last week, Griner was sentenced to nine years in prison by a Russian court for drug possession and smuggling after the athlete was detained in a Moscow airport with vape cartridges containing hashish oil.

Although she pleaded guilty, Griner said she had not intended to bring the banned substance to Russia. The Biden administration in May determined that Griner is being wrongfully detained. Meanwhile, Whelan, 52, was arrested at a hotel in Russia in 2018 on espionage charges that he and the U.S. government say are false.

U.S. Secretary of State Antony Blinken has previously said officials offered a deal to Russia that would bring Griner and Whelan home. While Blinken did not offer details on the proposed deal, media reports suggest the Russian prisoner who would be swapped is convicted Russian arms trafficker Viktor Bout, known as the “Merchant of Death.” Bout was sentenced to 25 years in prison in 2012 on charges that he schemed to illegally sell millions of dollars in weapons.

“It means a lot to know for a fact rather than just to hope a concession was made by the U.S. government,” David Whelan, Paul’s brother, told NewsNation Thursday afternoon. “But until Paul’s on the plane home, I’m not really going to get my hopes up.”

State Department spokesman Vedant Patel said on a call with reporters the U.S. is laser-focused and committed to any American wrongfully detained and that freeing them is a top priority.

The Associated Press contributed to this report.

This story is developing. Refresh for updates.