US Secretary of State Antony Blinken said he plans to soon speak to Russian counterpart Sergei Lavrov for the first time since the war in Ukraine began to discuss the release of detained US citizens.
"I plan to raise an issue that's a top priority for us: the release of Americans Paul Whelan and Brittney Griner, who've been wrongfully detained and must be allowed to come home," Blinken told reporters at the State Department on Wednesday.
Whelan has been imprisoned for alleged espionage since his arrest in 2018.
US professional basketball player Griner is on trial for a drug offence after being detained in February at a Moscow airport, days before Russian troops invaded Ukraine.
On Wednesday, the player admitted to the Khimki court in the Moscow region that she was carrying cannabis, but explained it was for medical reasons, the Interfax news agency reported.
Griner used the drug as a painkiller in consultation with a doctor, a common practice in the US, she said. "I had no intention of violating any law of the Russian Federation," Interfax quotes her as saying.
The Olympic champion, who plays in Russia in the US off-season, has been in pre-trial detention, which was most recently extended until December 20. She is accused of drug possession and faces up 10 years in prison if found guilty.
In order to facilitate their release, Blinken revealed that Washington had put forward a "substantial proposal" to Moscow several weeks ago, and that the two sides have been discussing it since.
"I'll use the conversation to follow up personally and, I hope, move us toward a resolution."
Blinken did not elaborate on the proposal.
US broadcaster CNN, citing anonymous sources, said the Biden administration has offered to exchange imprisoned Russian arms trafficker Viktor Bout for Griner and Whelan.
Bout was convicted in a US court in 2011 and is serving a 25-year prison sentence.
Blinken said he would also speak to Lavrov about recent deal agreed to by Moscow and Kiev to resume Ukrainian grain exports.
