Cherelle Griner, who met United States President Joe Biden last month, provided an update to CBS on the condition of the Women's National Basketball Association star after having a phone call with her.

"She's very afraid about being left and forgotten in Russia, or just completely used to the point of her detriment," Cherelle said.

Cherelle Griner added that Brittney felt as if her "life just doesn't matter" and alleged she could potentially be transferred to a labour camp somewhere in Russia following the hearing on October 25.

Brittney and Cherelle Griner have only had two phone conversations since she was arrested at an airport near Moscow in February as she travelled to play for Russian Premier League side UMMC Ekaterinburg.

Cherelle Griner disclosed it "was the most disturbing phone" call she has experienced and insisted "you could hear that she [Brittney Griner] was not OK".

Brittney Griner is accused of being in possession of vape cartridges containing hashish oil and she pleaded guilty, but denied knowingly breaking the law.

The United States considers Griner "wrongly detained" and has opened negotiations over a prisoner swap to facilitate her release.

However, these negotiations are complicated by the war in Ukraine, which the US is a strident critic of and has imposed harsh economic sanctions against Russia in response.

A prisoner swap also involving Russian arms dealer Viktor Bout has been mooted.

Cherelle Griner suggested that it is going to take "mercy" from Russian President Vladimir Putin to ensure her wife is freed.

She said: "I feel like at this point it's going to take Putin to have that same mindset and say, 'You know what, Brittney Griner - who came to my country for seven, eight years, and helped my country be recognised through sport, paid taxes in my country, helped my country - I'm going to sit at a table, and I'm going to be clear about what I need in return for her release,' so that we can actually get a meeting of the minds between these two Governments."