Russia is holding WNBA star Brittney Griner, Washington claims.

The Biden administration said on Tuesday that Russian authorities have wrongfully detained WNBA star Brittney Griner, signalling a more aggressive approach to her release.

The State Department had not gone so far before about Griner, who was arrested in February at a Moscow airport after authorities found hashish oil vape cartridges in her luggage.

"The US government will continue to support Ms. Griner," a State Department spokesperson said.

Griner, a centre for the Phoenix Mercury, is an offseason player for UMMC Ekaterinburg. They frequently play for teams that pay more than the WNBA.

Her detention came just days before Russia invaded Ukraine, prompting swift rebukes and sanctions from Griner's home country.

There is concern that Putin may use Griner as a political prisoner to gain concessions from the US.

The US government will now negotiate for Griner's return rather than wait for her case to be heard by a Russian court, 

Griner's teammates and supporters in Congress will be told they have her family's permission to raise her case.