(CNN) – The Biden administration has had communications with Russia to try and secure the release of Brittney Griner and Paul Whelan “as recently as within past days” said a senior administration official, speaking to CNN on Griner's 32nd birthday, which she will be spending in a Russian jail.The United States first put an offer for a prisoner swap on the table with Russia back in June – the details of which CNN exclusively reported – and “conversations have not been static since then” the official said.Despite the “pretty persistent” pace of discussions between the US and Russia to secure the Americans’ release, the official said that the Biden administration has yet to receive a serious counteroffer from the Russian side.“We have worked hard to try to demonstrate the sorts of things that could well be the basis for resolving this and each time we have articulated that it’s been met not with a serious counteroffer,” the official said.They said the Russians have countered with “something not in our control, not in our ability to deliver,” but did not go into further specifics.“They’re not non-responsive.
I would say that they continue to respond with something that they know not to be feasible or available,” the official said of the Russian response.The official said the US has used multiple channels for discussions with the Russians and conversations have taken place both in-person, by phone, and “through other forms.” The US has dangled multiple ideas for “things that could be in play” to urge a serious response from the Russians.As negotiations continue, Griner and Whelan both remain behind bars, with the WNBA player detained since February and the ex-Marine detained since December 2018.Griner was sentenced to nine.