WASHINGTON (AP) – Secretary of State Antony Blinken said he spoke to Russian Foreign Minister Sergey Lavrov by phone on Friday and urged Moscow to accept a U.S. offer to release former Baylor Bear Brittney Griner and Paul Whelan..

Blinken did not provide details of Lavrov’s response to what he had previously called a “substantial proposal.”

Blinken had publicly requested the call and revealed the existence of the offer to Russia – which people familiar with it say involves a swap for Whelan and Griner with convicted Russian arms dealer Viktor Bout.

Griner is currently on trial in Moscow, where she has been detained since February on drug charges. She faces up to 10 years in prison.

Griner testified at her drug possession trial in Russia that an interpreter translated only a fraction of what was being said while she was detained at Moscow’s airport in February and that officials told her to sign documents, but “no one explained any of it to me.”

The testimony by Griner, came on the same day that U.S. Secretary of State Antony Blinken said Washington has offered a deal to Russia aimed at bringing home the WNBA star and another jailed American, Paul Whelan in a sharp reversal of previous policy. Details of the proposal were not announced, though a person familiar with the matter said the U.S. has offered to trade convicted Russian arms dealer Viktor Bout for Whelan and Griner. The person insisted on anonymity to discuss an ongoing investigation.

Griner, testifying for the first time in her trial, also said that besides the poor translation at the airport, she received no explanation of her rights or access to a lawyer during the initial hours of her detention. She said she used a translation app on her phone to communicate with a customs officer.