Viktor Bout
CNN  — 

Hopes rose on Friday for a potential prisoner exchange between the US and Russia that could free two detained Americans, after a top Russian official said he foresaw the swap talks one day becoming “a concrete agreement.”

Russian Deputy Foreign Minister Sergey Ryabkov said that Russia hoped for a “positive outcome” on the issue of exchanging Russian national Viktor Bout, a convicted arms trafficker serving a 25-year US prison sentence in the United States, according to state media TASS.

The possibility of a prisoner swap is not only possible but is getting stronger, he said, adding that “and the time will come when the prospect will become a concrete agreement,” TASS reported.

However, the US State Department has cautioned against optimism based on Ryabkov’s comments, noting that Russia still has yet to engage in good faith.

“Ultimately here, actions speak louder than words,” said State Department principal deputy spokesperson Vedant Patel.

In July, CNN reported that the Biden administration offered to exchange Bout as part of a potential deal to secure the release of two Americans held by Russia, basketball star Brittney Griner and Paul Whelan. But Russian officials have requested that Vadim Krasikov, a former colonel from the country’s domestic spy agency, be included in the US’ proposed swap of Bout for Griner and Whelan, multiple sources familiar with the discussions have previously told CNN.

“Americans are demonstrating some outward activity. We are engaged professionally through a specially designated channel. We haven’t reached a common denominator yet,” Ryabkov told reporters on Friday, according to TASS. “But it’s beyond doubt that Viktor Bout is one of those that are being discussed and we certainly hope for a positive outcome.”

Responding to Ryabkov’s comments during a department briefing, Patel warned that “the Russian government’s failure to seriously negotiate on these issues in the established channels or any other channel for that matter runs counter to its public statements.”

“I’m not going to comment on specifics of any proposal other than to say that we have made a substantial offer that the Russian Federation has consistently failed to negotiate in good faith on,” he also said.

Bout’s lawyer, Steve Zissou told CNN Friday that this week has been “full of hopeful signs” for a potential prisoner swap

Zissou said Ryabkov’s comments could mean anything: that a deal might happen anytime, or it could just be a reflection of Ryabkov answering a question. Notably, Bout’s artwork that he has done in prison – which mostly includes sketches of scenes from jail – are currently on exhibit in Russia’s State Duma.

Zissou has received constant assurances from Russian officials that Bout is at the top the Russian list for a prisoner swap. When Zissou met with Russia’s Ambassador to the US earlier this year that assurance was reiterated to him.

Zissou believes that a trade that involves only Bout and Griner, would be successful and he has expressed that viewpoint to US officials, he said, but the US would not agree to that because they do not want to agree to any deal that would leave out Whelan.

He also voiced the view that that President Joe Biden’s position is strengthened with the midterm elections in the rear view mirror. Biden himself had voiced hope that the Russians would engage more seriously in the wake of the elections.

In August, Zissou told CNN’s New Day he is “confident” the proposed prisoner swap of his client is going to happen, adding, “Look, it’s no secret they’ve been wanting him back for several years now. They’ve been trying to get him back for decades.”

The US State Department, however, downplayed optimism around the negotiations on Friday, saying that Russia still has yet to engage in good faith.

“I’m not going to comment on specifics of any proposal other than to say that we have made a substantial offer that the Russian Federation has consistently failed to negotiate in good faith on,” State Department principal deputy spokesperson Vedant Patel said at a department briefing.

The families of Whelan, who has been held by Russia for alleged espionage since 2018, and WNBA star Griner, jailed in Moscow for drug possession since February, have urged the White House to secure their release. The State Department has declared that both Griner and Whelan are wrongfully detained.

US and Irish Embassy officials were able to visit with Paul Whelan at his remote penal colony in Russia on Wednesday, his brother said in an email.

On Thursday, Griner’s lawyers confirmed she had been transferred to a penal colony in Yavas, in the western Russian region of Mordovia, ending days of speculation over her whereabouts.

Her attorneys, Maria Blagovolina and Alexander Boykov, thanked everyone who has reached out in support.

“First, on behalf of Brittney, we would like to thank everyone who has expressed care for her,” they said in a statement. “We can confirm that Brittney began serving her sentence at IK-2 in Mordovia.”

“We visited her early this week. Brittney is doing as well as could be expected and trying to stay strong as she adapts to a new environment. Considering that this is a very challenging period for her, there will be no further comments from us.”

Previous reporting from Natasha Bertrand and Fred Pleitgen.