The United States said on Tuesday that Russia has “wrongfully detained” WNBA star Brittney Griner.
31 year old Phoenix Mercury centre Griner, was detained at Moscow airport on February 17 on drug charges.
The US Department of State said the safety of American citizens is among their “highest priorities”.
The White House’s finding represents a step-up in efforts to free Griner more than two months after she was seized in the Russian capital.
Griner has played for a Russia team during the WNBA off-season since 2015.
A two-time Olympic gold medallist, WNBA champion and seven-time WNBA All-Star, Griner is widely regarded as the best female basketballer of all time.