Russia has “wrongfully detained” WNBA star Brittney Griner, the United States said on Tuesday.
Phoenix Mercury centre Griner, 31, was detained at Moscow airport on 17 February on drug charges.
The US Department of State said the safety of American citizens is among their “highest priorities”.
“The Department of State has determined that the Russian Federation has wrongfully detained US citizen Brittney Griner,” said a spokesperson.
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.
She was detained after being stopped with vape cartridges containing cannabis oil, which is illegal in Russia, in her luggage.
Washington had previously been granted consular access but had stopped short of commenting on the nature of her detention.
Meanwhile on Tuesday, the WNBA said that all 12 venues across the league would feature Griner’s initials and jersey number (42) emblazoned on the sidelines when the new season begins on Friday.
“As we begin the 2022 season, we are keeping Brittney at the forefront of what we do through the game of basketball and in the community,” said WNBA Commissioner Cathy Engelbert.
“We continue to work on bringing Brittney home and are appreciative of the support the community has shown BG and her family during this extraordinarily challenging time.”